I've used all 3.
Beats Solo 3:
All 3 of these headphones are not accurate sounding at all. The Solo 3's have a "fun" sound signature with exaggerated bass and highs. Which makes today's modern trap/rap/hip-hop sound great and is also pretty nice for pop music. Rock and country music tends to end up quite a bit muddy with instruments blending into one another. House and techno tend to sound a bit boring because of the inaccurate bass response.
The earcups hurt after an hour or 2 of being pressed against your ears and whilst they do a fairly decent job of isolating noise with the music turned up it's nothing compared to active noise cancellation.
I found the build quality to be extremely crap. I had to get my first pair replaced for a loose headband that would slide itself out whilst being on my head and even after the replacement they still felt creaky and cheaper than they cost. It's probably fine if you're just using them at home and maybe at the office but you definitely won't be able to just toss them in a backpack without some kind of third-party protective hard shell.
Bluetooth performance is amazing. Pairing with the W1 chip is easy and fantastically convenient. Honestly, it's like magic, especially convenient if you also have an iPad, Mac or Apple Watch. Battery life is legitimately 1-2 weeks with around 3-4 hours of listening a day. Bluetooth range is also great, have personally tested it at around 20 meters with not even a slight drop out - the downside of this is that it can be easy to lose your phone because the music won't drop out for a while. Fast fuel is also an amazing feature - you'll get another day out of them with a 5 minute charge.
They do look pretty nice if that's a matter of concern for you. I got the matte black ones and found that they looked very classy.
Bose QC35:
Again, not accurate sounding. These lean more towards mids and high-frequency sounds. Great for Rock, Pop, Country etc. Hip-Hop can sound a little flat compared to other headphones. I find house and techno to be rather enjoyable on them, the bass is there but it's not dominating the track.
Amazingly comfortable, they legitimately feel like someone gently hugging your head. Not tight at all but yet they maintain and secure feeling and a nice seal against your head. Super light too - they're made from some kind of plastic composite that makes them feel light but still solid, they can definitely take a beating. I wouldn't go as far as to put them in a bag without the case but the included hard case is fantastic compared to the cheap soft one that comes with the Solo's.
Active Noise Cancellation is amazing, especially if you're on public transport or planes alot. Engine hums become silence. Murmurs of coworkers in an office, fellow students in a library, annoying family members at home become silent. It's not going to blockout things banging or being slammed and screams and alarms and sirens - but then again that's probably safer. Only downside of this is that some people report a feeling of "pressure" in their ears - not painful or fatiguing, just odd. It's difficult to describe, it's kinda like when your head is fully submerged underwater - but you'll know it when you feel it. It's most noticeable when watching movies or just having them on without content playing. It's fine with music going. I personally don't find it to be an issue at all.
Bluetooth isn't the greatest. They support simultaneously pairing and smart switching between 2 devices however i've found that the smart switching fails 25% of the time and so you'll find yourself in the Menu Bar on your Mac and the AirPlay menu on your iOS devices as well as the Bose Connect app trying to disconnect devices until it switches correctly. YMMV. I've found 2 iOS devices work more consistently than a Mac and an iOS device. Battery is okay, you'll be charging every 3-4 days and range is about 10-15 metres tops - you won't make it to the other side of your house.
I hate the look of the Silver ones but I have the matte black ones and I think they look classy without being obnoxious. Kind of like a designer suit - from a distance you can tell that they're something special but you're not quite sure exactly what they are.
Beats Studio (Don't have as much experience with these):
Sound signature similar to the Solo 3 but with less exaggerated highs and lows, might even go as far as to describe them as "boring". Also less exaggerated highs and lows does not mean that they are accurate at all. Accurate headphones can still be fun and engaging. These are not.
Much more comfortable than the Solo 3's, but not as light and luxurious feeling as the QC35's. Build quality is mildly better than the Solo 3's but at least they have a much better hard case to go along with them.
Active Noise Cancellation is there but nowhere near the level of Bose. Bose really is the industry leader by far in Active Noise Cancellation.
Whilst I didn't use them for very long, in terms of Bluetooth all the W1 pairing features are there and just as great as they are on the AirPods and Solo's. I'd assume range is just as good, battery life however is known to be somewhere in between the Bose and Solo's due to Active Noise Cancellation (this is a recurring trait of all ANC enabled headphones). Fast fuel again is also great, getting another day of charge in 5-15 minutes.
Interesting colour options, I personally wouldn't touch anything other than the matte black ones in this range. I find the others incredibly tacky. They are pretty fashionable and recognisable and are a bit of a fashion statement.
End of the day I ended up sticking with the QC35's as comfort, build quality and ANC were the most important things for me.