Thanks.

Can get Ditra but Dural is supposed to be cheaper, according to Dave, who is always right about everything

Dural is often cheaper you're right, and if you buy enough it's really cheap. And it's does the job just as good if not better.

Wetdecs.co.uk: Shop Online for Wet room, Screens, Tanking kits, Wet room shower tray formers. or PM dave if you can't get in touch. Tony from WetDecs seems to be pretty busy with other things as of late.

IIRc he wanted an extra £80 or £90 for the membrane (app 5m). I'm getting the Ditra for just over £10 per metre plus VAT. I only need around 3 metres and I'm getting some Kerdi tape as well.

CTD will cut you a length. I've asked for one 3 metre length as opposed to three 1 metre lengths. I'm probably going to cut one to the width of the floor then trim a bit off the 2nd to suit. TBH I could probably do it with 2 metres as I'm not using it on the former (Tilux supplied by Wetdecs).

Wetdecs has supplied me with 6 inch waterproof strip to stick down to seal the floor against the wall. I guess there should be no issue bedding this onto the Ditra?