I have trouble trying to encourage tradesmen when doing their tiling to have some tanking let alone epoxy grouts, I mention that it's waterproof and a little dearer but good and could save any problems at a later date, They just don't get it:yes:
epoxy by name poxy by nature. this product is for the true tiler if you are a diy then you may need some help. however do not use this product if your tiling is poor and you think the grout will make it water tight (it wont) good luck.
Seriously. Epoxy is overkill in almost all domestic applications. Tanking in combination with cementious adhesive and grout is a far far better solution.
Also, don't expose yourselves to epoxy without proper protective gear; the fumes can cause you nerve damage, among other things.