Dawsons should not expect you to return the items back to them under your own steam.
They should be offering to collect the items from you.
When returning goods, I would recommend you take note of any consignment numbers used by the couriers, so you can track the goods.
This can guard against the good old "We ain't had the stuff back yet mate" if they won't refund until the goods are back with them.
I can sort of understand that comment coming from retailers in this climate though, as many people do try to play the game and get refunds for stuff, but not return it.
I'm obviously not suggesting that is the case here!
In my experience Dawsons don't stock, and just don't generally understand Hi-Tech equipment.
They are good for overpriced accoustic guitars, and sheet music, and maybe a tambourine at a push.
I'd probably just go elsewhere in all honesty.
I don't "hate" Dawsons at all, I just wouldn't trust them with my time or money when considering any equipment that could be considered out of the ordinary or remotely hi end.