I have an old Kenmore serger from the 80's. I tried not to unthread it - just tie new threads on and pull them through. I recently upgraded to a new serger - Babylock Evolution. It had the two features I wanted, air threading and coverstitch. I do not sew knits but have to alter everything I buy. Coverstitch is the double hem stitch you see on ready to wear knits. This machine is expensive - about $2500 - it will be the last one I buy. I don't quilt on it but I am willing to look into it. I have grandchildren to sew for and do home dec. sewing, tablecloths, napkins, etc. One tip I would give is keep some muslin squares next to your serger. Every time you use a new stitch, make a sample, staple it to an index card, and write your settings and the project you used it on. Saves time not having to look up your stitch and settings every time. Go try them out and buy the best serger you can afford.