While one could look at the number of maintenance updates since X3 came out as being problematic, (was actually X3a), I would suggest that it means they have been busting hump to address things as quickly as possible, instead of waiting for gathering more patches into a single maintenance update, and I think this is a GREAT thing.
In the first place, the X3a was really quite solid, and they have been SUPER attentive and diligent at working on the minor things that have been included with the 3 updates - and another already coming.
I think that by far the consensus in the forum is that folks are quite happy that the maintenance is as frequent as it has been.
My recommendation is to go ahead and pick up X3 as soon as possible, and you will be quite pleased with it.
Bob Bone