Chris,
I would recommend the LMS3900. I do not have the solid column but if I were buying one today would get the solid column version.
They come with a belt drive and I've had no maintenance issues with mine. I did a (approx $40) upgrade on the pulleys to increase the spindle speed and added Igaging didgial readouts on all three axis (I highly recommend this).
Mostly do aluminum and have done some steel on this machine as well.
GG67