I'm not sure what retired means. Superseded by a newer version or model? If so, it doesn't matter. What matters is whether the machine has the features you are looking for and "feels good" to you when you sew.
I would not purchase a machine on eBay unless I had at least tried out the brand, and preferably that model or a close model, to make sure I like the stitch quality, the sound of the machine, etc.
For those with budget limitations, I think it's much better to go around to local dealers and see what they have in used machines. Often you can get a better quality machine with more features if you buy used instead of new.
It's also a good idea to check out reviews of the specific model you are looking at.
http://www.patternreview.com is a good place to do that.
I have a FW and 301. I'm wondering if there is something you are doing wrong with both machines that produces the bunched up stitches on the bottom, as that is not typical of those machines. Are you sure, when you insert the bobbin in the bobbin case, that the thread is going in the correct direction? As I recall, the FW needle threads oddly (from left to right? it's been a long time since I had it out).