Speakers for Simaudio Moon I-5

I'm starting to build a system from the ground up and I'm really quite new to it all. The only piece I currently have is the Moon I-5. From here I want to buy speakers and a cd player -- both used. I'd like to get the best bang for the buck.

I'm not very concerned about the cd as I plan to go cheap (a relative term here :) -- probably less than $700. The speakers are another issue. I want to buy something I can live with for a long time.

My current room size is "medium" -- an apartment that I will be in for the next few years until I buy a home. I mostly listen to what most would consider "rock" music. I'm a guitarist and I like listening to others guitarists but with the right setup I'm sure I'll enjoy some classical and jazz.

I'm thinking I'd prefer to go with monitor speaker vs floorstanders and I've been to a few shops to sample what they have - though, since I'm buying used I'd really prefer to stop wasting the saleperson's time.

Short and sweet....out of the few speaker I've heard (dynaudio, B&W, Thiel) I loved the Dynaudio S1.4

Which leads me to believe that the 1.3se might be a great used buy. Although I'm a little concerned about the Moon's ability to drive these speakers. I would greatly appreciate any recommendations or advice. There are so many choices out there it can be overwhelming. That along with buying used/untested can be tough.

Any help appreciated...

John