The LS25 was introduced in 1998, the same year as the Reference 2. The REF5 was introduced in 2009 and the REF5SE in 2012 probably. I got these data from the ARCDB (Google it). So LS25>REF2>REF3>REF5>REF5SE is a lot of steps up. I have no doubt the REF5SE will sound better.
ARC LS25 mkii vs ARC Ref 5se
I currently have an LS25 MKII. I was wondering if the Ref 5se would sound better? Anyone have experience with both?