I recently had both a Colerain and Rice in my hands. Due to a very poor job by the supplier, I returned the Colerain.
Honestly I don't see what is so special about Rice. I have a 42" C profile swamped 54 caliber with round "radius" rifling. The outside of the barrel looks like it came right off the mill, which it probably did. I don't see why that matters. Draw filing is rather small in the grand scheme of things, and the Colerain had the same finish on it.
The bore on the Rice looks just fine, but it's not like I look at it and go "wow, that's fantastic". It looks like any other rifle bore, good enough, not polished, it doesn't need to be. The C profile Rice is markedly thicker than the C profile Colerain. I suppose that doesn't really matter, it's a matter of what you want.
The big one for me is the breech plug. The plug on the Colerain was fine. The plug on the Rice... well there's no way a human put that plug in. They must have set specs, and a machine torques them. I ended up having to create a jig, and wrench, with 4 foot long cheater bar to get my Rice breech plug out. It left a mark on a barrel flat, which I'm not real happy about, but hopefully I can hide that when finishing the gun. I then fit the plug myself, but in no way did Rice do a good job with the breech plug.
All that said, I've got no real problems with the barrel. As long as it shoots good, I'm happy. My point being, there's nothing special about Rice barrels. They aren't even made of good steel, the stuff is rather soft. It's good enough for blackpowder uses, but not exactly high dollar steel. Green Mountain steel on the other hand is very tough. You can tell right away with a file. If they sold swamped barrels, I'd say they were superior to Rice. The only Douglas barrel I got to shoot had a very smooth bore, either lapped from Douglas, or got that way by shooting. I don't know much about Rayl barrels, but from what I see, they are superior to Rice in every way.
For the cost Rice is fine, same as Colerain. If you wanted the best, I'd go for Rayl.