Thanks for your input @philbert. TBH 150mbs is about 5 times what my broadband currently provides, so it's well within my requirements. I didn't realise that WDS was a 'one-sided' thing, I was...

@Somnus "But if you connect EAP to a router via an Ethernet cable, and want to connect C20 to EAP's Wi-Fi, I think it's worth a try. Not sure if they are compatible." - that's what my question is...

I have a EAP225 Outdoor AP, and I would like to connect it to my Archer C20i as a bridge. Archer supports WDS, but EAP225 doesn't. Is it possible, or do I need to buy more hardware ?