I like them and wish they would stay. That said, they make sense at the start of an x-pac while levelling and as heroics between hitting max lv and the first raids.
I do like more 5 mans a sthe xpac progresses (like ICC and HoT) but it feels like there is no clean solution what purpose they serve.
- should they be ball breaking hard so only hardmode raiders can crack them and drop raid equivalent loot?
- should they be somewhat hard, doable for Pugs and drop raid equivilant loot as a catch up mechanism - and be a slap in the face of all raiders?
- should they drop sidegrades and badges?
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I will admit that there are no hard 5 mans, but being able to form your own group has always been there.