Got this achievement today. 17minutes.
Thats me 100% completed. The advice I would give is not to follow too closely some of the youtube clips done by the 'professional' gamers. the ones who did it with a sub 5 minute run must have toiled away to complete the challenge like the rest of us and then tinkered with their strategy and their style of play to squeeze as much out of their performance.
Its better if you graft your way to the final wave and try to learn at least one lesson each time you get killed.
Thats what i did and today i had a revelation about how to deal with those bogeys, to the point that i think i have an effective strategy to beat them that isn't available from all the youtube clips i've seen, and can be done by any competent game player.
I might upload a clip, but i can help you out with what worked for me, if you're having trouble message me - GT Ishtiyaq786