Agreed. Own the 9mm XD and will be buying the .45 soon. Favorite of all m guns imoIts been mentioned on this thread, but I'll have to recommend the Springfield XD(m). Its a great polymer striker-fired pistol IMO. It should fit comfortable in your budget as well.
If you can find one on sale or used, or don't mind stretching your budget, the H&K P2000 fixes a lot of the ergonomics issues of the USPc. Plus, it doesn't use the proprietary rail size that the USPc does if you ever plan on mounting a light/laser.
Regards,
Randy