I've never listened to a pair of JR-149's.
They sound
interesting
I don't think you can beat them at the price we paid - £8 the pair,
which is about US$12 I think. Like the LS3/5a, they are not full
range monitors, so you probably need the optional subwoofer if you
are going to use them other than for close-up monitoring.
I believe the original LS3/5a was designed to be small enough to fit
in BBC outside broadcast vans, with the aim of replicating the low
frequency roll-off that typical consumer equipment of the time had.
Today, audiophiles often use them with a tall, matching subwoofer
under each speaker.
Cheers
Daniel