well it was just too much strain for the 5s pack and the muggy, i ran the setup in my crt many times without any issues, the 1521 is 1577kv so on 6s it should be great i just wanted to make sure i wont have any issues with the next battery i buy but want it to be something i can afford to buy a couple packs.
Losi Muggy
medusa 36-80-2000kv
6s turnigy 30c
MMMV3
46ts/ 14-16p
spektrum radio