OP
This isn't an objective view and it's a bit long too.... Oh well.
I have had a pair of SHL5 for the last 14 months. As I have stated elsewhere they are by some distance the best speakers I have owned. Forgive my inept descriptions.
I previously owned a pair of Revel M22 Performa but following an Amp upgrade (E-212 > E-450) I felt that the speakers were perhaps the limiting factor in my system. Although the Revels had really improved with the extra power. They were decent speakers, powerful and clear sounding, I felt there was still a slight edge to the treble and a 'glassy' quality to the mid range.
I listened to the Kudos C10 (I think) at a dealers, but didn't demo any other speakers at home, maybe I should have but I don't regret it.
The Harbeths won me over within about 5 minutes and they keep doing so. They offer exceptional clarity but manage to do so in a non-fatiguing manner. I'm now confident if there is an edge to treble, it's because it's meant to be there (Primal Scream XTRMINATOR) rather than as an artefact (Aretha Franklin - with the Revels, mostly). The mid range is awesome and the bass goes deep enough for my room.
What don't they do? They aren't 'snappy' or 'tight', although the bass is deep, it needs some controlling IMO (partly the room too obviously). It could also be said that they don't do 'leading edge' or timing, that they are relaxed and / or boring. In my opinion that is because they offer a very transparent view on the system and add a minimum of their own character to the sound you hear. If you want tight snappy rhythms then strap on a pair of nap 140'S and an LP12. Other aspects of the music float my boat so I don't follow that route.
Finally, I have a pair of Grado RS1s and although they used to get a fair bit of use before the Harbs I rarely use them now. The SHL5 are excellent at low levels and I feel give just as much insight with better dynamics.