I like anywhere from 300-400cc. They have plenty of power to get the job done. Mines mostly used around the farm, fixing fence, spraying, whatever. I wouldn't want a bigger machine because that's more weight. I've got a Honda rancher and a kowasucky bayou. The rancher is lighter and pretty easy to man handle and get unstuck or over a big log by yourself. The bayou is basically a cinder block on wheels. Hell, it even handles like one.
I don't really know why you'd go larger. Unless you were towing quite a bit of weight great distances.
