I got a ADL Stride recently, which drives my RS1 really good, in my opinion, on par or even better than RA1 (in memory). Not sure about SR125 but it won't be bad.
However the Stride is not made for sensitive IEMs. On my SE530, the hiss at quieter background and gaps is almost unbearable. So if you use the combo for both SR125 and other IEMs, it's not a good option.
Also, it's not cheap, depends on your budget.