Some good feedback here, Candle Power forums has a wealth of knowledge on the subject.
I started into the flashaholic addiction about two and a half years ago with a Fenix LD20, then purchased quite a few of the inexpensive lights (Fenix, 4Sevens, Dereelight, etc.) fast forward to now and I think I might have 3 left out of about 20.
For EDC (I work in an office) I prefer customs, usually either XP-G or XM-L emitters and powered by RCR123's. For when I'm snowmobiling, ATV'ing or just going to be in an abusive environment I carry a HDS Ra clicky, or an old Novatac 120T both have been modded.
Here are some pictures of my customs :