My regular stick is the Blackout V2 XTD, and while it's too soon for me to make a full comparison, I'd say they're close in many aspects. The main issue is it's balance point being 2-3 pts more head-heavy (the TW specs
here &
here confirmed my findings). The Blackout XTD V2 is known for being quite "whippy", and that helps me when I play the younger, big-hitters, as I can often find myself rushed during baseline exchanges. I've only played twice so far, once was doubles indoors, the other singles outside on the clay.
Indoors it felt great. Good serves, really solid on returns, and while I suffered at the net, it had nothing to do w/ the frame. I was just "off" that morning (I switched back to my Blackout after 1 set and still was off). I serve & volley in doubles, so there weren't many drawn-out ralleys.
Outside, on the clay, I was really feeling the difference in balance, especially on the forehand. Countless times I was lagging on my shot, and having to "slap" it. Granted, my opponent was hitting really well, and I was a bit tired, but I switched back to my Blackout for the 2nd set, and after 2 games, got my timing back.
I added a 2nd overgrip (I like mine between 4 3/8 & 4 1/2) and then measured it vs my Blackout (which I've highly customized). My Blackout XTD is 349g strung, but still 11pts HL (most of the weight is in the handle). Adding the 2nd overgrip, the Extreme is now 329g strung, 8pts HL, but the swingweights are identical (I won't bother with the actual numbers as my Briffidi hasn't been calibrated).
I'm playing doubles again tomorrow morning, so I'll get a few more reps in and will try to pay closer attention to things like power & spin.