Maybe I've been misunderstood. Actually my only concern is to be able to interpret my partner play, i.e. bids and signalisation (as far as possible with just a few indications in the profiles). I just know the French system (SEF) and not SAYC, ACOL, 2/1, etc ... so that's why I prefer to play with people using this system. Nationality is not at all a problem but factually most people playing SEF are French. Regarding the skill level, this not very important for me but some people care about that (i.e. table reserved for "expert or advanced" only). As far I am concerned I just want to not annoy good players (e.g. expert) with my mistakes.