I don't know why there is all this sarcastic discussion. Seriously, people, take a deep breath.
All things equal, primes are sharper and better than zooms. The problem is that not all things are equal. If there were a larger market for top-quality prime lenses, then we would not be having this discussion because the primes would be superior. Even so, I expect you could find a prime lens somewhere by some company that would be better and sharper than a zoom at any given focal length.
The problem is that if you have your 28 mm lens on your camera, and something happens suddenly in front of you that requires a 105 mm, you either lose the shot, you carry a second body with a 105 mm on it (and lose the shots that need 35, 50, 70 or 85) or you use a zoom and get the shot.
To answer the original poster's question... there really isn't a good manual-focus wide-to-tele zoom that I've found. If you want a lens with that sort of range but good manual-focus feel, the professional AF zooms are awfully good. The 28-70/2.8 is not quite as long in range but will give you decent manual feel on a manual body. I routinely use my 80-200/2.8 and 17-35/2.8 on manual bodies and I don't find myself wanting for more "manual" quality.
The 28-105/3.5-4.5 itself is pretty good too. The focus throw is fairly short, but one can get used to this.