I have a 1.1Ghz Gold rMB, just got it on Monday. It's my first Mac, and it certainly doesn't feel slow or laggy to me. I have noticed a few stutter animations in Yosimitee, but from what I've read these occur in even the 13" pro's as Yosimitee can be a but unoptimized.
But just doing general work like web browsing, typing documents, youtube, etc., I notice no slow down. And those tasks are exactly what I bought this machine for.
Now, before anybody jumps on me for saying the reason I don't notice the slowness is this is my first Mac, consider this. I have a very good desktop I build myself that runs Windows for gaming, with an overclocked quad core i5, 8GB RAM, SSD, GTX 680. I have a 120z monitor and love playing games at closer to 120fps rather than 60fps, so I do have a fast machine and am very capable of noticing frame drops and effects of a bogged down machine. But I don't see any major problems with my rMB. Now, I don't have file vault enabled, maybe that has something to do with it.
Also, where are you getting $1700 from? It starts at $1299...