Are you talking about end game norm? or end game elite? (remember in elite mobs have more hp, more resist, more damage, etc). Cuz in Elite, in my experience, I find I cant ignite nothin'...Not even a Imp Trooper (granted they are lvl 60, but still...a freaking imp trooper), nor can I kill one in less than an hour. In the new patch 1.2, they are going to re-balance NM Act 5. I've tested it out on TC, and while they do retain the same lvl...it has become more manageable killing them; However, still almost impossible to ignite, and when u do get a success ignite, it only lasts for a sec.