Ok, so barring Jazz, all these guys came yesterday, and I have some thoughts on the PotP figures.
I want to start with Starscream. I absolutely adore this guy. The robot mode to me is the best part, and I love the proportions on him. It's funny, it's hilarious, he's on the computer desk glaring at me while I type this. It is fun, and I like how the proportions are so inflated. It sort of has an Animated vibe to it, and I loved that show and those designs. I like having his feet as giant shoulder pads with the rifles sticking out. It's fun! And he feels inflated in a good way, pleasing to hold. jet mode isn't that good, but I wasn't expecting much, and combined mode is fun. Sometime soon, I will combine him again and have the legs assume arm mode, so I can give him chicken legs like his movie self.
Overall, I am very pleased with Starscream. I like him.
Grimlock is next: great figure overall. fun robot mode, fun dino mode, and the combiner mode is boss. I am especially liking his combiner head, it's sweet. I don't have an issue with him combining, he feels good, looks good, and I am happy minus the sword thing, but I have that taken care of.
Dreadwind is a nice aerialbot retool, and I am liking him. One thing I will say is I'm not too big a fan of moving the wings to the legs for the combined modes, it removes the sleekness some. But overall, good, and I want Blackwing so I can combine them.
Swoop is everything I wished for. the only complaint here is that his ankles are somewhat loose, but other than that, fantastic.
Slug: pretty good. I wish the dino mode was bigger, but he's still good.
And now with that Blastoff looking more and more likely, I will get him, and use Dreadwing, Blackwing, my spare 3 wheeled from a flea market Dragstrip, and most likely Starscream to make a new combiner.
EDIT: I have one major complaint about the new combining system: the feet. I have had issues with Victorion's feet since I got her, and I cannot have the cars as legs, otherwise the ankles will not work and she falls right over, and that same thing is happening here. The ankle tilt takes away just a bit too much stability for some guys to work as legs. my Swoop topples the combiner form thanks to the ankle give on his own mold and that of the foot piece. Same thing happens with Dreadwind, and with Jazz to a lesser extent. I would have preferred the CW HFG approach than the new ankle tilt feet, my combiners are gonna suffer in the standing department