When I did my basement I just put the sheet rock up to the joists. It
might not be perfectly level, but to the eye, you really can't notice
plus you will gain the maximum headroom. I also put in 1'X4' recessed
flourescant lights that fit perfect between the ceiling joists. It
really gives it a nice finish look. I also have a few hi-hats.
The biggest problem I had with putting up the sheetrock is that some of
the joists were not exactly 16"OC, so the edge of the sheetrock
sometimes did not land exactly on the joist. But that was easily solved
by nailing a 2X4 on the joist to "extend" it so now the sheetrock
landing on solid wood.