We're only going up to about 6 MTRs and the Loads at that height will be under 1 Ton. The max load on the racks is 1.6 Ton which will only be at the bottom levels. From step one onwards it is less than a Ton. The usage is going to be light, probably an hour or two a day so don't expect failures soon but all of them have reasonably good support and dealer service out here.