Best Martin for the price?

Hey guys, I've been playing guitar for a while now and I usually buy $500 Fenders and such. But I've decided to lay down the money and nice Martin for around $2,000-$2,600. I've been looking around and I've found a few: D-18, HD-28, and the GPCPA3. Any thoughts on those guitars? Also, if you have any other guitars in this price range to recommend, that'd be much appreciated. Thanks!