I guess its time to give my impressions on the Devil Breakers
Overall just with these 3 DB it is a massive improvement over the Devil Bringer system in 4 regardless of how you feel about having to break them to switch. Now I will evaluate each Breaker individually. Overture is a good standard introduction DB. Its not as stylish as Gerbera and Punchline and have nowhere near as much utility and depth as those 2 but it works wonders as a finisher and a massive damage dealer. I'm still getting the hang of its context sensitive Battery attack. It also has strong knockback at walls compared to your other attacks. The best DB for dealing consistent damage against Goliath especially with jump cancelling Battery (still getting the timing on that) and parrying his rush attack feels so damn exhilarating and stacking bombs on him to deal massive damage is a perfect way to clean off a good chunk of boss health and I was able to easily stack 4 bombs. I want to see if you can stack up to 5 before the first one detonates. Dealing so much damage to Goliath seems to stagger him too. Either I crossed a health threshold that causes the stagger or perhaps high volumes of cumulative damage in certain areas (either his head or his balls). Using High Shot to keep enemies in the air makes JCing with Battery a lot easier too since High Shot stun locks the enemy in place. The Exploder bomb is a great set up tool and you can plant it on certain objects like vehicles (I've been trying to plant it on the vehicles and debris that Goliath picks and either toss or eats and causing it to explode in his hands or stomach. It can plant on those objects but he never picks them up in time). Still trying to master the High Exploder technique (where you shoot High Shot and perform Exploder immediately afterwards so it explodes on contact). Overture while not as cool as the other 2 two still has ton of uses and I pop it in from time to time.
I never bought the hype for Overture until I learned that you can JC Air Jockey so you can cancel the first Air Jockey to make the next Air Jockey come out faster and repeat this process (but works better if you're more under the enemy and stops working the moment you're above them). It makes Nero boost through the sky at Mach 10.
I probably should use Petal Ray and Stamen Ray more often and learn how to effectively use them. Petal Ray doesn't seem all that effective outdoors and Stamen Ray makes for more cool-looking finishers. Can deflect projectile attacks very stylishly. I didn't really learn this one very well so I should probably more into it. To me Gerbera's best usage is its ability to scoop up enemies with its dash and especially in confined spaces that is where the party happens just dragging a bunch of Hell Caina's around taking them for a wild ride

. I didn't use Gerbera as much of a dodge function (since it has less i-frames than jumping) but more for maneuverability and controlling both enemy and player positioning. Also the neutral Jockey is the closest in DMC I've seen to a force push and makes for amazing set ups too.
Lastly Punchline is probably the show stealer. I thought when I first saw it demonstrated at Pax I thought it would be janky and a total pain to operate its flying features and at first it was but once you learn there is a whole moveset to this weapon Capcom for dumb reason didn't include in the move list than is when it opened up as probably the best Breaker in the demo for me. Just the sheer amount of tricks and moves you can perform on it and once you learned these tricks, how they work, mounting the arm and unmounting and the timing with that and chaining that into other combos, and how to chain them it makes the riding part so much more smooth and stylish. Its honestly Tony Hawk skateboarding at that point. I even used the Rocket Arm to outrun Goliath's suction tornado vortex. If it was just the Orbit/Round Trip and its Break Age moves then it would've been a Badass Breaker but this makes it a Smoking Sick Breaker. Also there is some exploit were you can cause the arm to orbit around you like summon swords but calling it back when you're next to the enemy it is orbiting that I've only triggered like 2 times that I am trying to master how to always replicate it but no one has yet to make a decent via explaining the proper timing.
Also just like Round Trip I've used it to damage enemies on its way back to me. Unlike Round Trip when used next to an enemy it knocks them away and feels more like a punch. Perfect for manipulating enemy placement and I can detonate the arm a few frames upon contact to make an explosive punch. It doesn't stop there apparently when the arm is orbiting a target and it explodes depending on where on the enemy is explodes it can send them flying in a multitude of directions. Punchline has as much moveset, options, and depth of a weapon. Its a blast! The only nitpick I have is the fact its Boost Knuckle moves pretty slow (especially in the air) and doesn't seem to launch enemies when on land but can launch Goliath. It works perfectly for him....hmm needs to test out Boost Knuckle more.
Edit:
Overall I'm loving the Breaker system so far and don't mind how it is now it adds a different flair of gameplay that is pretty unique (granted a bit counter productive to these type of games) and offer a drastically different gameplay loop compared to everybody else. I'm still not 100% on board (would be if the Pasta Breaker was a default function) but I'm willing to wait and see when Nero has his full kit. His Devil Trigger offers some thing that might compliment this system.
BONUS: Criticisms
I just want to add some nitpicks and issues I have.
First I love how the Rainbow dropkick can be performed so easily now but I hate how the kick lack impact. It just pushes the enemy back a little. In DMC4SE whenever I could land a drop kick it send even enemies like the Frost flying and felt so satisfying. I guess that is the price of photorealism. It doesn't get in the way of combat and executing moves like many feared but now so many attacks lack impact when compared to the last games. Some attacks still feel impactful especially the Breaker moves but oh well.
The Camera even on the best settings I can make it is still wonky (better than the past games) but now its issue isn't the static camera now the camera is too dynamic and at times will screw me over not too often but it enough to make it noteworthy. My lock-ons sometimes disconnect and might even lock-on to a different target. When manually trying to lock-on to a specific target it would at times lock-on to the wrong enemy (this happens pretty often). Might need to play more and test how to utilize it or see if this is a genuine issue. Never noticed any issues with changing targets while locked on. Need to test that out to see if that is an issue too.
The demo stage itself is pretty alright. None of the enemies really push you and only the boss offers a decent challenge. Only the combat and its insane amount of depth for a demo is keeping me going after 20 runs so far (that is 20 completed runs, I've made about a dozen or so runs of just messing with mechanics, practicing jump canceling, trying out new tricks, and testing stuff). Another issue is all those long loading screens and other contrivances that I hope don't persistent in the final product makes replaying the demo tough for practicing and experimenting purposes.
That is all I don't really remember any other issues that I didn't already mention from above.