I absolutely adore my Yashica Mat 124G. Perfect condition, lens sharp as hell, have almost every accessories for it..... but what would i not give for interchangeable backs and a f/ 2.8.

As a student I cant afford both and I was thinking of getting a Kiev88 and give up on my Yashica, but I dont even know how comfortable or well I would adapt to it...
The Yashica is a pleasure to use, and the images it produces are gorgeous and bokehlicious while razor sharp in the center. The Kiev I have no idea, but it would be nice to have backs for low/high speed B&W and color....

Any ideas or suggestions? What should I expect from the Kiev? does it really matter?

Thanks!