The HD650 isn’t an “exciting” headphone, BUT it’s a timeless classic and REALLY good imo.
HD650 for relaxed warm sound with excellent midrange texture / vocal presence.
Sundara for lots of detail and analytical sound.
Either one is great, there’s no wrong answer, and it’s all about preferences.
EDIT: Sundara has slightly better imaging, and after reading some above posts I agree the DT880 is a great headphone for gaming also, but I think sundara has the slight advantage.
At this point I’m wondering if buying a pair of t50rp… or any of the variants to play around with until I can find a decent price on something would be worth while… Nowhere has open box and I don’t really wanna pay full price for Sundara or the gouge for Dt880s.
That or just get a cheap pair of Helios and do some pad swapping