Thanks for the interesting replies, everyone. At this point, looks like about half the voters have brewed a couple styles that they shouldn't have. Fortunately no one is doing it regularly (or else they're just not admitting it). The other half of folks are split between liking (or at least not disliking) something in every style and wisely sticking to styles they know they like.
People who've brewed saisons, sours, graffes, etc, have a pretty good excuse for doing this, I think. In a lot of places, that's the only way you're going to get a taste of the style. It's getting easier now, though, at least around here.
Never any style that I have regretted brewing. Particular beers yes.
Oh yeah, I think that's a lot more common. I had one---an ESB---that just didn't turn out very well. Nothing against the style, but mine just didn't do it for me.
I've definitely heard this sentiment repeated by numerous people. The key to a great fruit beer is to brew a great base recipe. Far too often brewers try to add fruit to sub-par recipes and the results are a mediocre fruit beer.
I had a really good outcome with a strawberry blonde ale. Especially by the end of the batch, I think anyone who likes a hefeweizen would have liked it. (I actually don't like hefes too well, but this was different enough.) The strawberry was present, even after a few months in bottles, but was quite subdued. It had a bit of fruity aroma/flavor, but I don't think you'd know what it was unless you were told.
That one was a bit of a gamble for me. Other than some lambics, I really haven't found any fruit beers that I like. (I'd consider the lambics to be their own special case.) Too many of them come out tasting like you mixed soda syrup until a beer. Definitely not my thing.