Phone Co-Op routers

I'm thinking of moving from BT to The Phone Co-Op for my phone & broadband (it'll be about £16 cheaper a month than current BT...).  Wonder if there's anyone here who is also using their services and router for streaming to a Uniti - any problems with set up? Also whether can alter DHCP ranges so that a NAS can have a fixed IP outside the DHCP range (as I currently have with my BT broadband V2 router.)

Thanks, Ian