How much is a good framerate for slo-mo recording?
In tecnical terms of Slow Motion, you can record at any speed, the fact is that actually slow motion... is achieved when each film frame is captured at a rate much faster than it will be played back.The technical term for slow motion is overcranking which refers to the concept of cranking a handcranked camera at a faster rate than normal (i.e. faster than 24 frames per second).
A third technique that is becoming common using current computer software post-processing (with programs like Twixtor) is to fabricate digitally interpolated frames to smoothly transition between the frames that were actually shot. Ciberlink PowerDVD uses that interpolation for ex.

Answering your question, you can achieve slow motion with any video recorder, the more frames per second, the better or smoothly... and of course you can use software post-processing to smooth frames out.

Hope this answer your question.