Personally I would go for either whatever's cheapest or something I know and trust. But yes, of course sex sells, if it didn't then the media wouldn't use it. If you want an example all you have to do is go to the 90's and the release of the Wonder Bra. Men bought it for their wives, girlfiends, other people's wives etc. just because on the posters and T.V. ads. there was some big breasted, good looking woman. And for the exact same reason women bought it for themselves - because if the girls on the ads. look that good with their breasts pushed up then surely they (the woman) can too.
Thinking about it there's also the Herbal Essences shampoo commercials, from more or less out of nowhere it became (and still is) one of the U.K's (I'm not sure what other countries it's in or how well in those countries, but...) best selling hair products because although it smells good, it shamelessly (though as a guy I did like them) used a girl having an orgasm in the shower to promote it.
So although sex may not be the only factor when viewing an advert as to whether you'll buy it or not, it does play a part, and that's why it's used to sell products over and over again.
