Well, things have moved on a bit.
I spoke to the Halfords C2W people who were much more interested in reading their script than listening to what I wanted to ask.
Essentially, I could get the voucher and spend it in store, but only on what they sell in store, or if I wanted any other bike order online from their "partner" company
Tredz...
So I eventually got them to email me their list of storage who accept their C2W vouchers to spend in store.
As a result I've been to Cycle Republic today, spent a very productive 20 minutes with an incredibly helpful member of staff, tried a couple of bikes for size and went through the various options. Plus, they'll allow me to top up the voucher if I want a better (more expensive) bike.
So the only decision now is do I go for the Giant Contend SL2 Disc with Tiagra, or do I stump up the extra cash and get the Giant Contend SL1 Disc with 105...?
Or see what clearance bikes they've got in when the voucher eventually comes through (first week in December, unfortunately...
). They had a Defy Advanced 3 Disc in today with £350 off...