Do I need a External uBec

[GorillaMaxx360]

I will be runing quark 125B, 1 servo(Hitec 5995tg ti gear), 1 reciever(spektrum), (2) 2s orion 4800 (total of 4s), quark cnc machined heatsink, and one fan(40mm 5v 5500 rpm). My question is do i need a ubec. Some people have told me that i need one, but when i looked at the bec information on rc monster i says you only need one if your exceding cell amount or servo amount. Now as far as i know i am not exceeding either because quark can go up to 5s and like more than one servo(i think) so do i realy need a ubec(external) for safe/efficient running. Thanks for opinions