You can try flashing them yourself, but I don't think I will bake them into the rom, I haven't talked to Benny about it yet anyway.
The EPST one works. I was about to post that it didn't work and it suddenly popped up. It enables ##778#
All it does is add EPST.APK to enable more special sprint codes to work. And it's tiny.
The Roaming one I can understand you being more Leary about because he is replacing Phone.apk. But the EPST one doesn't do anything unless you use it.
You can use Roam Control instead. Which works.
Note: The PRL files have to be on the internal SD.
Sprint phones these days are useless without it, IMHO.
EPST.APK has been around forever. It's only the last couple years Sprint stopped including it on consumer phones.
Roaming is a hack. EPST.APK isn't, it's just putting back functionality Sprint used to include and doesn't replace or change anything.
You can almost think of it as a license to use the extended codes.
I think I would have dropped Sprint by now in favor of Verizon if this capability didn't exist.