I went a bit the other way around. Switched from RedHat to Gentoo ca. 2002, and used it for about 8 years, when I started using mostly Macs, and some Ubuntu installs (less time to dick around with build flags and long compile times). Just last week installed Manjaro on a new system, and it seems really nice. I'll probably switch my home laptop from Ubuntu to it (or plain Arch, maybe)