I have one, rarely use it. Problem is that most of the serger companies (from what I understand) have gone under. Mine came with a VHS tape so I know how to thread it (sort of), but no manual. Therefore, I have absolutely no idea how to adjust the tensions/what each dial is for/what each thread is for/etc. I think I just need to sit down and put a different color thread on each spindle (mine will do 3 or 4, I guess), sew with it, see where each thread lies, then start playing with the tensions. Time is a problem right now, but I would like to be more efficient at using it. I don't like how loosely the serge stitch is when I work with it.
Just my 2 cents' worth. Good luck.