JL Labs vs. REL

I don't think the new series of REL are in any way inferior to the older series. I actually think the connector's, the cabinet finish and in fact the overall sound is superior. Obviously, YMMV.

Since the S series is rather new, you may not find anyone with experience with the two of them.

Then people, please share your experience with the older R series, thanks!

I concur. REL is the best sub (for music) in the market.
JL Audio does a nic job for HT applications only.

Yes, the Britainia series were outstanding! Keep me posted and happy listening!