what 5.1 rom do you suggest (besides CM)

Hi there,

I used CM a long time on my s2, but I just cannot get CM 12.1 to boot on my device. I would like to try out 5.1 though, so do you have any suggestions for a nice stable rom that can be compared with CM?

LG G4 materials? (besides the back cover)

Considering getting a G4 and was wondering what the frame is metal? Looks like metal, but I've been fooled by the S4 and S5 before...