Are you planning on taking this thing out and putting it through it's paces as far as riding on dirt trails and through the mud? If so, it's not really gonna matter much WHAT kind of protection you put on the polished parts, because that sand, mud, debris, etc. is kinda eat it away quicker than a jackrabbit on a date. The strongest coating I've heard of, (a little bit more involved though), is to have it anodized. You're actually coating the aluminum with a micro-thin layer of plastic. No matter what product you eventually settle on, this rule seems to apply to them all:
High Shine = High Maintanance
Low Maintenance = Low Shine
Just my 2 cents. Hope that helps.
