You can't really go wrong when you combine Sonic and pinball.
It was by no means a great game (and still isn't, as a matter of fact); even for a Sonic-themed pinball game, which SOUNDS like a great idea (because who didn't love the pinball levels from the original sonic games?), but it has a certain charm and simplicity to it that actually makes it likable. Despite the few glitches, the insane difficulty level (one aspect I kinda like, but most won't), and only 4 levels and general lack of variety between them, there's a pretty fun and challenging arcade-style pinball/platforming hybrid to be found here.
It's been re-released multiple times so there's a good chance you already own the game in some form, but if not, there are worse virtual console purchases you could make. For $8 (that's what it costs, right?), I'm getting a fair bit of enjoyment out of it.
I'd say overall it's a mediocre Sonic title, but with heart (unlike today's mediocre Sonic titles..).