Thoughts on max urls in sitemap

I've had my "max urls in sitemap files" set to 50,000 since I originally installed this a couple of months ago. But now I'm wondering if that's too many, and if setting it to a smaller number might make Google more effective.

What are your thoughts, vbseo guys?

It seems to me logically that setting it to a smaller number, say, 10,000 would allow Google to more deeply hit the site. But maybe not -- I'm no Google expert.

50,000 is fine.. I wouldn't go higher then that with one sitemap