#1
Well I just made a new cover... where I play steve vai's Tender Surrender...

I find it really hard to play this song with my guitar...

The picking seems harder to do and the legato stuff is way worse... everything is painful...

If u need to know.. my guitar is a brand-less strat copy.. probably just 100USD...

http://www.youtube.com/watch?v=WM5jQgaYNv4
#2
Pretty awful. And it's not the guitar (even though the tone is just as awful for this piece), you're just playing way above your ability.
#3
i agree with dynamight, you should work on your technique before u go for a song like that, work on your bends, legato and such. I have a guitar similar to yours and its not the guitar thats holding you back, its because your not experienced enough to tackle a song of that calibre, but with practice you can be.