Ok, I'm honest, and yes, for me cost is a factor.
I am replacing my bathroom suite out of NEED rather than WANT, (I put my foot through the bottom of the old bath that was not supported properly - which unfortunately I didn't find out until it was too late).
I don't have 'Trade Contacts' and I can't afford to pay someone enough to come in to do it and expect them to do a decent job, but I do enjoy DIY, I'd like to think I'm pretty good at it, and I ALWAYS try to learn everything I can about a subject before even starting to embark on it, (just ask Richard, I've asked him enough!)
When it comes down to it;
I have 2 young children so bathtime is WET, and also will have an overbath power shower.
Each end of the bath is a wall, covering 1m wide (before reaching the door or window depending on end), and 2.3m tall. Then the wall beside the bath is 1.7m long and (of course) 2.3m tall.
HomeLux Membrane:
5m x 1m I can get it for £43 a roll.
2 full height lengths per roll, I'll need 2 rolls (10m2) = £86 + jointing tape.
WP1:
8Kg pot, covers 8m2 is £35.
If both do the job equally well, as it's only a domestic bathroom (not somewhere in permanent use) then the WP1 seems the solution to me.
Also as the bath 'butts' up against the wall at both ends I tend to think that something that is painted on will add less thickness to the walls, than having to apply a membrane using adhesive.
I'm not cutting corners, I'm not scrimping, but if there are 2 potential products I can use, one is expensive and probably overkill for my needs, and the other is cheaper, then hell yeah I'll go for the cheaper one
Well... you said you hadn't heard an argument for using a paste, so thats mine
No offence intended at all, and I hope none is taken, just wanted to let you know my reasons for going WP1