5200SE is the speaker I'd always hoped the 5200SL would be.
The improvements in bass started with the 5200 EBA firmware upgrade but the SE improved more. I have the clamp rings as I elected to trade my 5200s in rather than upgrade them with the kit. Bass is nice and fast / tight, not something you could say about the vanilla 5200s.
I therefore cannot testify to the difference the clamp rings make but given the jump in performance I suspect they are a significant part of the improvements I'm hearing.
Only your own ears can hear the 'real' difference though, so make the journey or do what I did and just jump in blind. No regrets,
The SE electronics and tweeter are genius. Just waiting for enough MQA material for the next big step!