Well, they are very different yoyos.
Let me go into some details about the two.
Skyline: The skyline is a very much undersized yoyo.
It has very smooth play and is lighter than most yoyos, or at least feels lighter.
Due to its light weight, this yoyo is great for trying to do faster tricks and trick combos.
It has a small ridge like that of an 888.
Very nice player to throw around for fun.
3A: feels a bit light but works
5A: just a tad too light feeling for 5A.
All in all, an awesome player, just a bit light for me
Superstar: The superstar is an oversized yoyo, it is one of the smoothest yoyos ever and is a normal weight, maybe a tad heavy at most.
It has a slight “H” shape like that of a g5+, infact, the yoyo almost looks like a g5+, but it plays better in my opinion.
Grinds very well.
Its weight is great for long, smooth combos.
Super yoyo for super play cause its a super star
5A: Feels a bit too large for me
A wonderful, smooth yoyo
Both yoyos are nice.
Of the two, I like the superstar much more, but that is just my opinion
If you want to follow my opinion, get a superstar