Is 150 PSI a Good Compression Number?

I've got a 12.5 HP Intek (model no. 219907, manufacture date of 2005) on an old-style Snapper rear-engine rider. It's not running smoothly, & I'm trying to zero in on the problem, so I performed a compression test on it. B&S doesn't publish compression specs. Instead, they recommend that you take the engine to a service ctr. for a leak-down test. That would be a hairy hassle for me, plus $ I don't want to shell out, plus who knows how long the service ctr. will have it? As stated in the title, I got a reading of 150, & I was wondering if an experienced person here could tell me whether that's good, bad, or merely acceptable.

Also, a little bit of gas leaked out when I unscrewed the hose from the adapter in the spark plug hole. Is that a big deal?

Is 150 PSI a Good Compression Number?