3 stars

Pros:
Adds hieght
Adds bulk and stability
Looks alot better then it did without the upgrade kit.

Cons:
Parts not all matching. Screws to feet didn't always match lucky if i got 2/4 to match to hold the extensions on.
Way to much force required to attach the new shoulder extensions, was afraid i would break the toy.
Little wing flaps broke on legs but i could careless about them

I hate to leave a 3-star review for any upgrade kit I've bought as the rest have been 5-stars. However, after some hard work this upgrade kit pays off.

The cons:
The instructions were not included. All I got was a one page fold out showing off the finished product on Superion and some vehicle modes.
Some parts of the hasbro mold broke in the head, though I can not say this was because of the upgrade kit with 100% certainty. I was able to get the head fixed with super glue afterwards though.
The new head, at least for me does now allow him to transform back to vehicle mode. The new head is too bulky to fit properly for transformation.

The Pros:
The kit adds some real bulk to Superion. The added articulation in the arms is awesome! Having the new waist piece fixes any issues of the chest collapsing on itself so that's very pleasing to me.The pieces added to the feet help with the height for the combined mode. With everything added, Superion looks a lot better next to his nemesis: FP Bruticus.

Since mine didn't come with any actual instructions (not sure if my case is unique), this took a lot longer to apply that I would have liked but I was able to figure things out and it really paid off. Superion looks amazing! I am impressed with this set. If you want to give your FP Superion a better look, this is the way to go!