I just bought the White 2000 ATS serger. It's my first serger and I was as conflicted as you.....didn't want to spend a ton, read lots of good reviews of the 2000 ATS but also read some bad ones. I also had owned a White sewing machine that was AWFUL so I was kind of brand shy. I was tempted to buy the babylock 450 (costs around $350 on sale) but I went to a dealer to see it & threading it made me want to scream!!! You need tweezers and a ton of patience!!! Threading the White is pretty easy --- harder than a sewing machine (well....duh...there are 4 spools to thread!) but no tweazers needed and it's pretty easy.
Also I liked that you could quickly switch to doing a rolled hem (which I plan to use since I sew lots of houseware/decorative stuff) -- with some of the other sergers you actually need to change a plate (with a screwdriver). I also looked at the Simplicity serger but, again, you need to change the footplate for a rolled hem. Oh...another reason I bought the white was because it came with some extra presser feet which I haven't had a chance to try out. While I've only had this machine for a week, I've cranked out about 8 dipes, some bum sweaters, some PJs for my lil' guy, a bunch of soaker pads, and some cloth table napkins (w/rolled hem). While I can't say how this will hold up over time and use, it was easy peasy to start using and I had NEVER used a serger before. I basically pulled it out of the box, plugged it in and serged my first dipe (it came pre-threaded....). Since then I've rethreaded it a few times and changed the needles, and tested out some other stitches. I view this as my "starter" serger and if I find I use the heck out of it and it doesn't hold up, then I can save up and buy a higher end model -- I just didn't want to put a lot of cash in up front since I had no idea if I would really use it much --- I can tell already that I'll use it a lot! Oh....I paid $300 for it from allbrands.com --- no tax or shipping.
GL with your decision. I know how hard it is to decide. Let us know what you get.