I haven't heard the Martin Logans. I have not heard the KEF Reference 3's. I have owned a pair of KEF Reference 1's. The top end was slightly laid back. The bass was rather boomy. The bass in the Reference 3's is probably tighter. The thing I loved about the KEF speakers was that the listening position, or sweet spot, was much larger than most speakers. If you are putting them in the living room and are expecting multiple listeners, I would strongly recommend KEF's. If you have a laid back system, be careful because the sound may be a bit dull. I have now gone to B&W's, but I miss the KEF's at times. I guess it comes down to what is important to you.
Kef vs Martin Logan
I know these are two completely different speakers, but I've fallen for both of them and I would like someone else's opinion. First I am comparing the ML SL3's to the Kef Reference Model 3's. I have a Sunfire Theater/Cinema Grand setup. Will the ESL's work well with the Amp I have? Also space/ placement is a concern. My room is medium sized (15x 12 w/ 10 ft cielings). I'm not trying to shake the building but I don't want to think I'll be wasting my money if the speakers are restricted by acoustics. Any input anyone has would be welcome.