As the other replies said, CFOP is much more developed, and one
heck of a lot more resources available for it, because so many more people use it. But that's not to say that you can't be just as good with Roux. It'll just take you more work to do so.
Just look at some of the stats of the
top Rouxers in the world.
2 3x3 singles in the top 100 in the world, 2 3x3 avgs in the top 100 in the world.
OH is a different story, tho: 13 OH singles in the top 100 in the world, and 20 OH avgs in the top 100 in the world, 5 of those OH avgs in the top 10 in the world, all by Rouxers.
So, Roux is definitely feasible, even more so for OH, it'll just take more work to get there without the same amount of resources or near as many other people who use it to help.
All that said, I still vote for CFOP.