Sometimes it comes down to availability and after sales support. R-Tech always have a massive waiting list and are too far to travel to for some folk. Personally I love a good road trip and if the map is good, the return journey is going to be a lot more fun!
There are indeed a lot of remaps available. Revo, Superchips and APR are the most well known off the shelf tunes, and R-Tech and Stealth Racing are the best for rolling road tunes.
I know from experience Revo are always helpful on email and responsive, as are Superchips. Haven't tried APR but they also have a good reputation.
I've had a custom maps and Revo. The custom map made bigger numbers but it didn't FEEL much quicker on the road, but the Revo was smoother as it wasn't pushing the turbo as hard, and they seem to have nailed the areas under the curve for daily smoothness, which some tunes can ruin.