Your most intense, vivid, and memorable dreams occur during REM. I don't know why you'd want to be lucid anytime else. Even if you managed getting lucid from a non-REM dream, stabilization would be tricky at best, and it's likely the dream wouldn't last longer than a minute or two. But if you want crappy LDs badly enough to go through the hassle of a WILD attempt right when going to bed, all the more power to you. I'll stick with my lengthy and quality LDs, thanks.