I am a big fan of the 301s, I own quite a few. The throat space is 7 1/2inches which is really not too shabby. The 301 has a knob that lowers your feed dogs so you may free motion quilt. I am not an expert at FMQ but I find that I do not have as much "eye lashing" and issues with the vertical bobbin which the 301 has. These are very sturdy machines with the same beautiful stitches that the 221 has. The 301 has gears instead of the belt and the motor is much stronger. I love that it is almost impossible to throw off the timing. You do not need to get service, just oil and grease. They are not at all fussy about thread and you don't need to worry about surge protection-no motherboard. The only drawback is that awful button controller-same as the featherweight. I find it terrible uncomfortable at retreat or extended sewing. Two of mine have updated foot controllers, just remove cord from button controller and wire it to just about any controller that you find/ want.i would rather sew on my 301 than my Janome 6600. I think the tension and stitching is exceptional. Everything is so solid, no plastic.It seems that I can maintaina really consistent seam allowance. I believe that is also why everyone loves their featherweights. If you decide to purchase one,here's a few pointers.
I have purchased 301s in Singer desks for as little as$50- prices vary a lot ! The originals in cases are more expensive.Watch craigslist to avoid shipping. Make sure bobbin case is in machine-these are the same ones used by the featherweight and the originals are the best but Expensive- more than buying the machine sometimes. The presser feet are slant shank. Featherweight feet will not fit.