My Bernina sewing machines were and are a 1260, a 1530 and now a 220. I just purchased the 220. I haven't really used it yet but it weighs a lot less than my other two machines. I am going to take it on my retreat next week. The serger that I broke was a 400D. My new one is a 1150MDA. I used to do a lot more garmet sewing. The serger is great for that. I am mainly using this one to make Linus quilts. I do them envelope style on the serger and then machine quilt them on my sewing machine.
If you are willing to learn the ropes you can do a lot of sewing with a serger. It will do eveything a regular sewing machine will do except buttonholes. I have used it to make pillows with a ruffle and a zipper. Every step was done on a serger. The majority of mass produced clothing is done on a serger. It is so much faster than a sewing machine. The only drawback is that if you make the garmet to small there is no going back as it cuts off any fabric past the seam line.