Sure enough, I've been living here in Colonia del Sacramento for almost a year and a half, and as such, I've had the opportunity to visit this restaurant quite a few times. I even applied to work as a waiter there. However, the few times I've eaten here, I noticed it had its positive aspects as well as its negative. Sure enough, the food is ok, I guess, although quantity very clearly overpowers quality. If you know a bit about Uruguayan cuisine, you know they're just trying to get away with their poor quality meats by replacing traditional dishes with cheaper, faster imitations of the same.
Nevertheless, if you enjoy eating at places like McDonald's or perhaps Perkins (Although I think I'd prefer Perkins), and want to experience fast food in a different country, then by all means, eat at Mercosur. Like I said, the food isn't BAD, it's just not as good as one would expect. Of course, you can't compare the prices, as with most fast food restaurants. As far as Mercosur goes, it's pretty much the best place to go if you want a cheap and filling lunch or dinner. Not recommended if you want to try out REAL Uruguayan cuisine, nor for a special occasion.
As for the service, I suppose you could say it was just fine. Nothing out of the ordinary, but good enough nonetheless. As a waiter myself, I suppose I can see why the waiters at Mercosur might seem disinterested. They slave away all day to try and keep both their managers and the clients content, something which is near impossible. They ought to get a medal. So, if you do choose to dine there, feel free to complain about the food's quality if your chivito comes with soggy fries, a burnt egg, no bacon, and a steak as thick as your hand (The Chivito sandwich traditionally comes with an almost paper-thin filet mignon steak, otherwise it's not a chivito, it's a steak sandwich.), but please, give your waiter a break. And remember, the tip isn't extra. It's part of his paycheck, as it is in most places, including the place where I work (Which I will not divulge)
Hope to have been of help! Cheers, and good eating!
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