Of the two boats mentioned, I would probably also choose the Mad River. But I concur with those who suggest checking the used market first. If you are prepared to buy one of these boats new, it is quite likely that you could find a used Royalex or fiberglass composite tandem for the same price, or less. If you are lucky, you might even find a used fiberglass/Kevlar composite for the same price or a little more. I think a good quality composite boat would probably suit your needs better.
Having said that, I think three layer polyethylene canoes are an acceptable choice for a boat that is going to reside within a short carry or drag from the body of water it is to be used on. They do tend to deform a bit with age, but this doesn't really affect their performance terribly much if you are not planning to paddle all that fast or far. They are awfully heavy for one person to portage any distance or regularly car top, however.
All three layer polyethylene boats and Royalex boats tend to acquire scratches, shallow dents and grooves with use.
Having said that, I think three layer polyethylene canoes are an acceptable choice for a boat that is going to reside within a short carry or drag from the body of water it is to be used on. They do tend to deform a bit with age, but this doesn't really affect their performance terribly much if you are not planning to paddle all that fast or far. They are awfully heavy for one person to portage any distance or regularly car top, however.
All three layer polyethylene boats and Royalex boats tend to acquire scratches, shallow dents and grooves with use.