Expensive tiles to get a failure on. All failure is expensive, rather the customer paid for the correct adhesive than have to pay for a new all for a few pounds more.
In the description it says that keraquick adhesive must be used to fix quartz tiles. I was thinking keraflex was just a slower drying version of keraquick and that the s1 version was just a more flexible version of keraflex and would therefore be OK to use. Maybe it needs to be keraquick mixed with latex rather than water. I am guessing tile mountain are recommending this adhesive as it is a brand they stock. I'm not sure who actually manufacturers the tiles so can't find a manufacturer recommendation.
I did find some information on the porcelenosa website regarding adhesive used for their DQS tiles which are similar. The info states 2 part adhesive and also points out that it is the water in conventional adhesives that cause the problem.
I guess I now understand why a slow setting adhesive is not practical.
I'm beginning to think that this job may be better handled by a pro or maybe a re-think on the tile choice.
Glad I posted on here before diving straight in though. Could have gotten myself in a right mess.
Or because they over-specify to make sure that risks are minimised. I can minimise my own risks by understanding why a product is specified, and choose accordingly. It's not corner cutting - it's rationalising.