I think it would be cool to have one but not practical if you didn't have a designated dealer. If its on a cart you'd have to move the cart around so people could use it and if its built into the table have a spot where everyone can reach it and not have it get in the way of chip stacks, splashed pots, cards, etc.
Also there in the time factor. By the time someone loads them into the machine to shuffle you could pretty much be done shuffling by hand if you are a decent shuffler. Way around this would be two decks so one deck is shuffled while the other is in play etc I guess. Alternatively you use two decks and have the person behind the dealer shuffle the next deck. That's how we do it in the bar league I go to sometimes.
If I had a ton of extra money I'd put one in a table just to have it but I don't know how often it would get used.