Am I the only one who seems to have about a 50% drop rate on the moxxis bouncing pair and tinas hippity hopper grenades🤣
For a second data point, I have seen exactly one of each of these drops myself. (I’m still not sure how to get the most out of Tina’s grenade).
I have only ever seen two Moxxi’s Pair - once on my first character FL4K while levelling up so it was only a level 20.
My Zane found one in the DLC that was anointed with the On Grenade Thrown, increased damage for gun, grenade, and melee. Was quite happy with this one and it is my goto grenade for everything right now 
I get them all the time, I don’t even pick them up anymore. For every dozen legendaries I farm I get AT LEAST one of each. Is there a different legendary that you guys seem to get all the time, or is that just my luck and everyone else is a little more varied? Maliks Bane is another one I don’t even pick up anymore.