I am no expert. However, I own three 301A machines and one 401A.
I love, love, love my 301 machines. I am just getting geared up to FMQ with my black one. My 7 year old granddaughter loves sewing on my black 301 too. They are light weight (just a little heavier than a Featherweight), and have a sturdy built-in handle on it.
My 401A is a work horse. I have repaired seams on our boat canvas covering. It glided through those multi-layered seams. Can't go wrong with either one. Currently, I don't have a 500.
Ditto what tessagin said. Read up all you can while you are hunting. While you are searching get a feel for what those machines are actually being sold for. Some are asking too much. My last 301 I purchased for $150 about 2 years ago in my area. A lot of people barter to lower the price. I didn't. The machine was extremely clean, had a clean original case with attachments. I felt it was worth every penny.
Last edited by SewExtremeSeams; 06-08-2015 at 11:37 AM.