I really like the CB300F. I bought it last month and have 1300 miles on it now. There are some quirks with it but they are minor: My kickstand is a bit too upright, doesn't allow the bike to lean quite as much as it should. It's a thumper, so it vibrates a little and is also a little twitchy in 1st gear. With very aggressive riding, mine chatters a little when you let off the throttle quickly at say 8000 rpms. That's it. Oh, the clutch is rotated a little far forward and down than on other bikes, but I just haven't got around to rotating that back a little. These are not major issues. The bike is sound. It is very capable. Top speed so far for me has been 85 mph. It will do a little more, but it's not a fast bike, but very capable of highway speeds. In fact you could just stay in the passing land and go 80 mph if you want.
The light weight at 348 lbs. wet is important. It means the bike is easy to handle, easy to move from side to side, and less likely to fall over if you make a mistake while stopping or with slow speed maneuvering, something that requires a lot of practice to get good at. In other words, you can get off balance a little with the 300 and still recover. Can't recover from heavier bikes. Stop a traffic light and put your foot down on gravel and it slides out...you and the bike go over. Have the front wheel turned and hit the front brake. Bam, the bike falls over. Start to take off and the engine dies and the bike lurches a little, you lose your balance and bam, down again. People drop bikes just moving them in and out of the garage. Then good luck getting a heavier bike back up. This light weight is huge for a new rider. Light weight also equals fun. I am not opposed to heavier bikes, but I expect a lot in return for the added weight. This is why I am not a fan of the Honda CB500F. It weighs 72 lbs. more than the CB300F with very little in the way of performance gain. The FZ07 a much more powerful bike weighs under 400 lbs. wet, and the CBR600R, the supersport race bike is still 10 lbs. lighter than the Honda 500.
There are a bunch of good light weight bikes: The Honda CB300s, the Ninja 300 and in a couple of months the Yamaha R3. I don't think you can go wrong with these. I'm just under 5'7" and about 140 lbs, so I like the shorter seats too, which these all have. The CB300F seat ht. is 30.7 in. and I can flat foot it easily. If someone was tall and heavy, you might be able to handle a heavier, taller bike. If I were tall, I would look at the supermotos like the Suzuki DR-Z400SM with a seat ht. of 35 in.