a SA XD-40?
I had a bi-tone XD-40 with the 4" "Service Size" barrel.
It was a good weapon, and my first pistol. I ended up NOT being a fan of the .40 cal and sold it, but not because of any particular weapon deficiency.
It's similar-ish to a glock, with the added grip safety. If you prefer that extra reassurance, I say go for it! Even if you don't, $500 is a fair price for a new XD (at least around here in CT) and I'd still go for it...