Jan-Z's is a world away from the flashy action in Tumon. It isn't going to be high end cuisine, but if you want a relaxed environment with a nice outdoor, covered deck, Jan-Z's is a good place to stop.
I've made a habit of going to Jan-Z's every so often--while my favorite time to stop by is Sunday breakfast. Jan-Z's does a really nice spicy marlin dish, and they will make it for breakfast if you ask. If you get to know the servers, they are very friendly and will engage you in a nice conversation.
Service may not be fast, as others have noted, but you're in southern Guam and the pace of things is definitely more laid back down here. The bar inside is a bit of a Navy bar due to the fact it is not far from the back gate of the Apra navy base (lots of memorabilia) and while it usually isn't busy, it is a nice casual place to stop for a drink if you live nearby or are making an island tour.
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