rule number one.
always go to a local bike shop (they're the the small, oily ones) if the guy's a "salesman" and isn't isn't a little dirty, hasn't seen the road or the mud, he can never give the best advice.
As for rule number two, I can't think of one at the moment.
you asked about the downside of hybrids. I can't think of any for general usage they're great. I had one until it was wrecked. I can't advise you on those models as I don't know them.