Would there be any conflicts with associated tube gear?
Using the RCA units for your player hasn't been an issue at all for me (as I have tube monoblock amps). However, I tried the hanging-wire amp versions on the amps and did not hear any benefit at all (but no noted degradation either). So, I used the amp units on my humble 20 year old Onkyo receiver on my video system.
Overall, I have heard the most benefit of the RCA units on CD players....less on stabilizing internal circuits of preamps and a slight benefit on stabilizing the circuits of solid state amps/receivers, etc with the hanging wire versions.
So, the only one I can candidly and wholeheartedly endorse are the RCA units (I have the $218.00 MR273 and the $49 original R103 and I can tell you that the pricier one does indeed offer better performance) on CD players. Only on CD players without tube outputs...and it's probably hit or miss with DAC's. But, WOW, it made a Sony DVP-s7700 player/transport, which was absolutely miserable to listen to beforehand as a player (even after substantial power supply modding by Empirical Audio) into listenable with the (then) R103 I had used back then.
Dr. Dao tends to ship fast and does answer questions I've found....I think he takes back returns too if not entirely happy.
All the players today are really pretty good....the MR273 can take them up several notches for $218.00 (less than most DAC's). The MR273 replace your IC's too, and added savings to you

John