The 75-150 f/3.5 Series E zoom is reknowned for sharpness, even if the E-line build quality was not so hot. It is an AI-S lens. Make sure it's in good condition if you get one. Mine was great looking, but there was no stiffness at all in the zoom, if you tilted the lens without a firm grip on the zoom barrel it would slide in and out by itself. I had to take it to a good repair shop and have it worked on so that the zoom would stay put (I believe they put some thick grease in the zoom mechanism).

The 35-70 f/3.5-4.8 AI-S zoom is also has an excellent reputation. I've had one of these since I got my late and lamented FM back in 1979. A very good lens with a very useful range IMHO.