I've got an '86 Escaper 4 cyl, fuel injecter, 4 sp, no ps, dash air, roof air been through the passes in the rockies several trips now, no problems. When I tow my two four wheelers that slows me down but I still get there, more relaxing driving without them though. As far as air if you ever go south into hot humid states you will have to have air or you will sweat like a pig day and night in the summer months. I'm from Kansas and the southeast part of the state is unbearable. Now I have been in some of the western parts of Kansas that are not to bad when the sun goes down and it's dry and a breeze is blowing. Another great thing about roof air, some campgrounds can be noisy and with the windows closed and the air on you sleep through the night without hearing a thing. The only time power steering would be needed is when parking, I would like to have ps then. Once you are moving the steering does not take much effort. On the highway there is no difference. My mileage has ranged from 13 to 23 mpg most times it is about 16-17 mpg. Oddly I seem to get some of the best mileage at high altitudes. Well, I have rambled on long enough. Mike