I love both these guitar players, but regarding to the question whos better, its a close call coz both are in the same vein. Both neo classical players, both virtouso, speedfreaks. Although Yngwie has an edge in speed, impact and influence, Jason has an edge in creativity, choice of notes, and versatility ( he can play great metal along with Marty, unlike Yngwie which is stuck in his neo style). Not to mention Jason is younger.

But no matter who you believe is better, these two are still one of the very best and a great inspiration for all players...total package musicwise and speedwise.

Some trivial facts:
Jason performed Yngwie's " Black Star" during their schools talent show.
Jason wrote " Serrana" and " Perpetual Burn" when he was 18.

Yngwie is acknowledged by other super shredders, namely
Paul Gilbert, Chris Impellitteri and Joe Stump as their main
influence and their inspiration to play at the next level.
- According to Steve Vai : " Yngwie is on top of the heap
when it comes to precision speed picking "
(Guitar Player Magazine)

Wow !!, Ive never heard a superb player like Vai, who is already very good in his own right praise another player for his technique. Thats coming from a guitar master so Yngwie earned my respect in that matter.