Well, you can call it a girls bike, or a beginners bike, but I'm neither and I love my 658.
Does it have it's faults? Certainly. I wish the front forks were better and that the rear suspension was better (I'm starting to work on that), but I chased one of the best riders I know thru the back roads of Vermont a few weeks ago and he didn't loose me even on stock suspension. Now, my R1200RT has Wilbers suspension front and rear so it's no slouch in the handling department, but I still prefer to ride the 658 unless I'm headed for somewhere "far - far" away where I know I'll be riding a lot of slab and thru a lot of weather to get there.
The 658's combination of reasonably low weight and reasonable power makes it ideal for the back roads of New England. And when you find that one of those back roads turns to dirt, it's no big deal, you just keep on motoring along. The only performance change I've made so far was dropping to a 16 tooth front sprocket (with the stock 41 tooth rear) and to my mind that really helped it on the back roads. It probably hurt it on the slab, but it didn't appear to hurt my gas milage, it gave me a usable 5th & 6th gear, and it helped it's low speed dirt road performance.
Are there better "speciality" bikes (touring, sport, off-road, etc)? Absolutely! But if what you want is one bike that is just as happy commuting to work as it is headed out onto the back roads for a week, you'd be hard pressed to find a better bike and I imagine the F700 is just as good.