No major issues for me. I have an RG750 which uses 9-42 and is tuned down to E flat. I don't think you should use 10's unless you tune to D, but the 9-42 set isn't perfect. I'd suggest buying strings in singles and doing this: 9-12-16-24-32-44.
You'll see that this feels better because the
string tension increases gradually as the strings become thicker. On a regular 9-42 set, this doesn't happen because the B and thick E strings are a guage too low.