I thought the mirelurks were pretty cool, loved blasting their soft faces.
Wanamingos though would put the cazador and death claw to shame as Wanamingos are fast and hard to kill.
According to the wiki, Deathclaws in Fallout 2 (or one kind, as there was a weaker version also called 'Deathclaw'), were faster, had more health, dealt more damage and healed slightly faster than Wanamingos.
Only things they were lower on was armor class/DR/DT.
Their resistances are basically double of the Deathclaw, but they have half as much health, are slower and do less damage.
I think they sound preferable to a Deathclaw.
Poll