Schmelke is definately the best for $150 and under. Once you get to the $200 range many more quality cues are availalable. That would get you in a plane jane Joss or a McDermott with a G-Core shaft. Of course I am talking new.
Post that you have $150 to spend in the wanted/for sale section and you should get a bunch of good offers for used cues.
Ignoring price, I would recommend a cue that has interchangeable shafts.
Any cue with a Uni-loc, stainless steel collar like Joss, Pechauer (pro joint), or Schon.
My reason is that it is much easier get a new shaft and have it match up at the joint.