There's a lot of differences between various brands of sparkling mineral water, usually because of the different makeup of minerals in the actual water. I haven't tasted seltzer, but in general I think they are acceptable, although there are a few select brands that I find really good.

I usually find them even better when I have gone a long period without water, or if I have recently exercised. I avoid the flavoured ones because their acidity is a lot lower (as in pH closer to 1) than the unflavored kinds, and my teeth are weak enough as it is.

Club soda is one of the worst tasting sparkling waters I have tried, although there are multiple manufacturers of this too. I think it's only suitable for drink mixes, not to drink as a stand-alone beverage.

Perhaps I am just a sparkling water connoiseur.