Well, there’s a lot of good options out there. For me, I’m kind of an XD guy. They are super reliable and they won’t break the bank.
But that’s just me, everyone here will have their own preference. And they will all be good options.
I was going to suggest the 4” XD, but I have no personal experience with it so I felt I couldn’t comment.
http://www.budsgunshop.com/catalog/product_info.php?products_id=13342