I grew up around Guidos, and never had a problem with them, even though I was the geeky Jew with good grades. I always admired their confidence.
The silliest thing about all this PC hand-wringing is ever since the term "guido" first evolved in the 80's there have always been Jewish guidos and Irish guidos. From day one. Now, there are tons of Russian and Eastern European guidos, and even some Asian guidos. "Guido" has always been more of a fashion and lifestyle orientation than an ethnicity.