I think you'll find that the prices have remained the same at both Relax and Somjit (300 baht). The off fee for a private massage back at your room is still 500 baht at Somjit from what I understand.
Personally I always preferred the beds at Relax over the floor mats at Somjit.
As I'm sure you know these are "boy massages" specializing in "happy endings" - not professional masseurs.
A bit of trivia: The Thai woman who owns Samjit is the older sister of Beer who owns Boys Nightclub in Sunee (formerly Nice Boys).