I have had both electric and hot water underfloor heating. Both are fine at first, but the moment it goes wrong it's big trouble. Personally I wouldn't have either again, even as a gift.
we have had electric underfloor heatin under ceramic tiles now in 2 houses which we got from wickes and had no trouble as yet! it does make a great difference in the winter months.
I have it in the kitchen .. it is ok as a way of making the stone floor not cold but it is not enough on its own to heat the kitchen. So far mine has not given me any trouble but I have no idea how you would get to it if it went wrong !
We have underfloor heating in the kitchen, the polypipe type, which runs off the central heating. It has a seperate thermostat so control is easy and it warms the entire space, our kitchen is 30sq.metres. We also have electric u/f heating in our bathrooms because the area is smaller . If you have a reasonably large space I'd go for the polypipe; much more cost effective.