Viking and Babylock are both good brands. Just based on general comments over the last few years, I would say that Babylock probably has more popularity among quilters.
For reviews of specific machines, it's a good idea to go to
http://www.patternreview.com . Register there to be able to see all the reviews (it's free and they won't pester you). Click on "sm/serger" and then enter the brand name (e.g., Viking) in the window above that, then click "Go". Look down the list to find reviews of the specific model within that brand. Be aware of review quality too. I give more weight to reviewers who have used the machine for several months, as they have had a chance to try out all the features and run into any bugs. You can also get an idea of reasonable pricing from these reviews. (Sewing machines are a lot like cars in that Suggested Manufacturer's Retail Price doesn't mean a whole lot.)
Also check Amazon for the specific models you are considering; usually lots of good comments in the reviews there.