IMHO, Bernina anything is worth the money!! They are the Rolls Royce of sewing machines.
Kathi

I am a die-hard Bernina fan (sewing machines), but when it came to buying a serger, I chose Viking. I like the large D area, the space between the arm and the needle. It's more like a sewing machine in that respect, and I can reach through the D area with my right hand. My Viking is a 936 with a LCD screen which includes a sewing advisor. In other words, you tell the serger which stitch and fabric weight (woven, knit, light, medium or heavy) and the sewing advisor tells you how to set the serger tensions, etc. I love the machine!

Threads Magazine, August/September 2003, has an article regarding sergers with a comparison chart. Admittedly, it's a little old but will still give good information.

A serger that does a cover stitch and rolled hem is really nice - I use mine all the time.

Mary