Speaking of JBLs, the 4319 monitors are around the same size as the L100s and are a good, if not great used speaker buy. Not on the radar as much as the L100s and very popular in the Asian (mainly Japanese) market.
I still have a pair and when the L100s came out in their newer form, I asked the guys at Music Direct if they were better speaker and two of them told me it'd be more of a sideways move and one preferred the 4319s.
So many options out there so take your time.
All the best,
Nonoise