I bought a Viking, 2nd from their best; Huskylock 21. The store had decided to quit selling them so instead of paying over 1,000 for it, I paid 350 for it. Awesome price. Its not self threading but it has the guides on the front and a DVD so its really not that hard. The key to threading is that you cut the thread above the thread guides, then tie on the next thread you will be using and pull it thru. Makes it even easier. Its a great machine and couldn't believe it was so cheap.
While I was waiting for the CD to come in I went to a Babylock serger event thinking I'd learn lots about sergers, which I did. I also learned the one we were learning on which was their latest did things that others don't. I had the credit so I bought it, knowing that I could sell the Viking for what I paid for it and not lose any money. I didn't even register it so the warranty hasn't started yet either. I've just been so busy to list it anywhere. I think both Brother and Viking make great machines. The brothers with the air threading are on the expensive side so one thing you'll have to decide on is how much you want to spend. Plus some have dual setups, overlock and chainstitch, both of the two I have do but my old Singer doesn't. When I bought my Singer over 20yrs ago, I was able to manage the threading so I figured I could do it with the Viking, and it is easier now than it used to be. So if anyone who doesn't live to far away or is willing to pay shipping, I have a Viking serger for sale for the 350 I paid plus shipping if it needs to be shipped