I have both plus many more including feather weights. Love the 301.
I have not FM on it and I think it is hard to find a foot for it since it is a slant shank. I would think the 15-91 would be great for FM and for binding or work with a walking foot.
I would like a Singer 201-2 for FM but have not found one yet. The singer 15-91 would be my second pick for the FM. It has a dierect drive and a super good opening.
So set the 301 up for piecing and the 15-91 for FM.
A girl can never have enough machines. Have fun!
I agree with the above poster. If I could have only one machine I would take the Singer 301.