Most pretty good , will be a range dependant on how much you or client wants to spend. Would always recomend sealing the grout as this is generally cement based and is porous so can stain. If you seal this making the grout water and oil repelant ,you will give the client the best chance of maintaining this area long term.
Most important thing is how you maintain them once installed and what with. Whichever you use , the manufacturer will generally give detail on how to look after these products, call them and they can run through with you or they will have tech/ method sheets online to pass to your client.