I recently switched to nylon wrapped strings... they also have lower tension. But I mostly did it because I play a lot of americana / folk / rockabilly / blues / jazz and wanted a better slap sound.

Unfortunately they sound terrible arco so now I have to play cello when I play in my wife's orchestra. :(

[edit] it occurs to me that you're talking about electric bass... in which case nylon strings would be a bit strange ;) sorry about that.