It seems that high-end AMD graphics with free sync BenQ EX3200R (3 monitors) is pretty good value in comparison to the G-Sync monitors? Nvidia without any questions is great but it can be too expensive. The new coming release RTX is exciting news but once again preferably need a G-Sync monitor for the best experience. Due to my budget limits, I'm thinking of getting an AMD graphics and possibly 3x BenQ EX3200R monitors and hope that Raceroom has no issues with that?
Rather late answer, but if you are talking about R3E , Nvidia cards are probably a better choice. It's no secret that Radeon cards are generally slower in DX9 games. But, as a whole I am perfectly happy with my current RX480 and FreeSync monitor
I've run R3E with an HD6970 2gb @1080p with no problems ever, and currently with a 7970/R9 290 3gb with triple screen 5870x1080 no issues what so ever. Yes, I know, old and outdated lol...but every time I thought maybe I should upgrade, I was able to play most new games at the highest settings, and 2xaa, so I kept hanging on. Although triple screen gaming has shown me it's time for a new system. But, Raceroom runs good still, even though there are a few tracks that my pc isn't happy about when racing with AI cars...