I have a HW-19 MK III and the SDS and the SAMA.
The SAMA was the biggest improvement and the SDS was a meaningful improvement as well, but not as much as the SAMA.
Together they are great.
I also have a Rega RB300 Tonearm on mine, and it has been rewired with high quality wire and has the usual drop counterweight and endstub addtions as well and it sounds great. I tried a stock Origin Live Silver and while it was really nice, it was only marginally better than the RB300 with these modifications. I decided to sell the Silver and stick with my RB300. If you could get a VPI JWM-9 or a any of the upper level Rega Tonearms (RB600/RB700/RB900/RB1000) you'd probably be very happy with the sound
The SAMA was the biggest improvement and the SDS was a meaningful improvement as well, but not as much as the SAMA.
Together they are great.
I also have a Rega RB300 Tonearm on mine, and it has been rewired with high quality wire and has the usual drop counterweight and endstub addtions as well and it sounds great. I tried a stock Origin Live Silver and while it was really nice, it was only marginally better than the RB300 with these modifications. I decided to sell the Silver and stick with my RB300. If you could get a VPI JWM-9 or a any of the upper level Rega Tonearms (RB600/RB700/RB900/RB1000) you'd probably be very happy with the sound