Consider this as a third alternative: When faced with our basement finishing, we decided to not finish the ceiling at all. Iíll explain.
Our basement was fairly typical; decent height, but with various mechanical systems hanging below the joists like heater ducts and pipes, etc.. Finishing the ceiling with either drywall or suspended tiles would require some special wizardry to work around these items. With drywall, you can leave trap-doors for access, but in many cases, to have useful access you would need traps everywhere. Suspended ceilings offered access everywhere, but I had never attempted doing one.
I was flipping through one of my architectural magazines when I came across an article about someone who had turned a warehouse into a home. One of the pictures showed the ceiling, which they had left exposed, heat ducting and all. They simply painted it a matte-black. Although the ceiling in the magazine house was much higher than a normal house, certainly our basement, we decided to give it a try. After all, if we did not like it we could always cover it with drywall or tiles.
I took sch40 drain pipe, cut it in half, and attached it to the joist wherever electrical wiring ran, to cover it. In several places where the pipe did not work/look right, I simply made little plywood covers to blend in. where the basement walls went parallel with the joists, I simply aligned them so the drywall was flush with the joist above, when perpendicular, I simply finished the space between the joists with drywall. Then, I rented a vertical sprayer, and sprayed everything in the ceiling chalkboard gray.
We were surprised. It turned out great, and it was cheap. We ended up spending about $45.00 plus maybe 3 hours labor for about a 1100SF basement project. We mounted track and other types lighting up between the joists. A friend did the same thing, only he used a texture sprayer. I thought it was also very nice, but my wife did not like it, and it was about twice the cost of ours. Although ours held up fine, his texture began to flake off after a couple of years.