I've been using Groupons during my travels in Europe for the last 3 years. I've been generally satisfied with the experience and have definitely saved money. I try to pick up one or two per week of travel, as a guideline. I'm curious of your experiences with this sort of thing.
I've had very good luck with restaurant deals, particularly in France. Since I was based there for a longer period, they were easy to use. I do check reviews for each place before I buy. The only time a Groupon was not honored was also in France, for a restaurant in Aix.
Sightseeing deals are harder to come by that fit my interests, although I did snag a half-off Cliffs of Moher cruise in Ireland. I've got a bus tour in London coming up for next month, which I wouldn't have done if it hadn't been for the Groupon offer: £10 instead of £29.
I've bought Groupons for France, Ireland, Austria, Italy and now Britain - maybe two dozen or so by now. I've had to use Google Translate for Italy and Austria, but I managed. I find that about 2-6 weeks out from my travel date is when I find deals that can fit in my overall itinerary.
How do you use "coupon" deals?
Where else have you found similar offers, like "GrabOne" in Ireland?