How fast can you kill the Zero One Taskmaster?

I'm interested in learning minimum number of player-minutes required to kill the level 60 Taskmaster boss in the Zero One archive. Solo or team, doesn't really matter--I'm just after the rate at which he can be killed, ie:

- if it took you thirty minutes to kill him solo, the rate would be 30 minutes (1 player x 30 minutes)
- if it took you ten minutes to kill him with four players, the rate would be 40 minutes (4 players x 10 minutes)

So, how fast can you do it?

alone I've done it 15-20 min wid a upgrade master self buff/heal load did it about 10 times and still never got the gun , but on guns alone it took me 25 min and with a team of 3, 1 gun, one MA and a healer it took 10 min

a zion/mech/merv   panzy truce, about 60 on the platform, took about 10secs...so thats like

*gets out calculator*
10x60=600secs = 10mins
*hides calculator*

Yup done that in my head