@Yeah
I've only test driven the RC-F but from reviews and what I've read on Club Lexus, I would be happy with either cars tbh. Neither cars are the best performers for the price but does beat a lot of its competitors in overall package (mix of sound, ride quality and handling, reliability, etc). If you're going to be keeping your next car for several years (3+), the IS-F interior being a little dated, especially considering the RC has the LFA's inspired instrument cluster, I would be leaning towards the RC a bit more. If you don't care about the interior, exterior wise both look pretty cool. Just test drive them both, you'll know forsure then which one is for you and if the RC is really worth the additional $$ for you
I've considered trading in my RC-350 for the F after my test drive but decided to hold off. In less than a year I've already pay more than a third of my car off so I'm just going to keep it for maybe 2 or 3 years and pay it off fully and hopefully the GS-Fs will be a lot more obtainable. The RC looks better IMO, but I could use the addition shape and doors. I'll probably test drive one soon and see if it lives up to its price tag.