Tour Operators from Tashkent > Samarkand > Bukhara

Hi, if anyone has had great (and not so great) experiences with tour operators for the above, let me know. In doing some preliminary research, Advantours, East Site and Steppe Journeys keep coming up. Any experience with these guys? Any other recommendations?

We're a small group planning on a 2 week tour next spring, and want as much as possible, to have a say in planning our itinerary; or at least some flexibility in terms of time. We're also a multi-national group, so will need some help from a travel agency in sorting out the various permutations on visa requirements.

Thanks!
.s