Intial cutover: Toll Free Numbers, best to Port or to Forward?

Hello,   newbie here, working on implementation with a go live in about 6 weeks.   Still undecided whether to port our Toll Free numbers to RC along with a few hundred DIDs, or to forward the TFNs,  at least initially, as a safety net. Any feedback on your experience is welcome!    Specific question - has anyone experienced latency / other call quality issues with forwarded numbers?