Well, LS-240 would be much cheaper IMHO, there was a widely available EIDE version. Sure Panasonic has announced an EIDE model, but I've only seen the USB version from QPS selling.
I recently got rid of my floppy, and have found a moment or two were I could have done something had I kept my floppy drive. The best I can hope for now is the 2x LS-120 EIDE drive that can be had for $50 or so.
The one advantage of LS-240 over LS-120 (other than a 240MB upper storage limit) is that it can put 32MB on standard floppy media. Naturally, only LS-240 drives can read the 32MB-formatted floppies.
-SUO