I thought I had heard the frets on the 4001s will wear faster than other basses when using rounds, but that could be fallacy for all I know. I know the big issue on that bass is its ability (or inability) to support higher tension strings. I've got some low-ish tension flats on it at the moment.
When I got it back in the 80s it had Roto rounds on it, and some nice trenches in the frets. The neck was/is fantastic on it, though, (main reason I chose that particular one) and it still plays great despite the frets. Part of my motivation for putting the flats on was to stave off the looming need for fretwork... and I guess it worked in the sense that anything I put flats on I stop playing
. I've tried to like them... really!
My strings of choice these days are the EXL170s (nickel 100s), so I'll probably end up going that route on it.