My Opinion on the summer wave:
Rocka 3.0: The helmet is really weird looking. It looks like a rock or a ball of mud. But the white or silver 2.0 core makes up for the flaws of this set.
Nex 3.0: I'm glad they re-released this set, but the colours are not so good. They used a bit too many on him. For eg: orange, black, silver, green. These 4 colours do not blend at all.
Stormer 3.0: Julius Caesar much....? Yeah, that's pretty much it. I like the set, it's cool and compact. Love the claw arm!
Bulk 3.0: Now this is a huge improvement from the 1.0 version. He looks alot cooler, and I love the fact that LEGO got rid of that ugly gun arm.My favourite part about this set is the skull shaped helmet.
Stringer 3.0: Stringer has the same problems Nex has, only they are not so bad. My only complaint is the use of that random green armor on his shoulder, and the use of a black body for shoulder armor. I don't like the black body because it makes the arm look very sketchy and not finished. But I know that this set will look alot better when it's finished.
Furno 3.0: BLEH! Just BLEH! It's even worse than the 2.0
Rocka XL: This is Fire Lord all over again for me. It has the same problems Fire Lord had, only on this set it's even worse. The legs are extremely skinny and sketchy. I hope LEGO improves this set....
Witch Doctor: Now this is E-P-I-C! LEGO did a great job on this set. Everything blends in so nice, and the design is almost flawless. I love the spear/totem/staff thing.But I have the feeling that this set will be a bit more expensive than the rest, mostly because it looks like he has alot more pieces than an average titan set.
Scorpion: I love this wild beast(?) set, I will give my opinion when I see him from different angles. But yeah, the set is pretty good.Has a few problems, here and there but it's good and compact.
Raw-Jaw: Untill now, I don't like him. I hope that the final version will be alot better.
Fangz: Same as Raw-Jaw.
Waspix: This set is great! It reminds me alot of Gorast and Bitil. I don't get why LEGO make the Hero Factory villains (some of them) look like they could be a perfect Makuta character. But yeah, LEGO did a good job on this set.
I know my opinion will change alot when I'll see the final versions at Toy Fair but still, these are my opinions based on those pictures.