Well Alice Cooper wears them and so do a lot of other guitarists. They say it gives them better control then a guitar pick.
All that aside, to save you getting flak in your day job, I think you should go for a natural looking nail and get your girlfriend to put polish on for you out side of work, that way you can save the grief at those family dinners as well, get them used to the long nails first and then sneak the colour up on them at a later date.
PM zozo, if she's recomemding someone in your area then you know you'll get a good tech.