Parang / Knife

How to choose a parang to farming use. I think it depends on what is the nature of the job. There is the length, weight, size and the center of gravity. These are the two parangs that i've bought. The short one i use for weeding and general work. The long one i use for clearing bushes. The short one has a center of gravity close to the middle. It can not be used to chop medium trees as the seems to "vibrate" during the "chop". The long one has a center of gravity closer to the tip which is good for clearing a trial. You'll need a strong arm, due to the weight.
I keep both sharpen by using a sharpening stone regularly. The long one was blunt when new, so it need to be grind off first with a grinder otherwise it'll take ages using a sharpening stone.