i've been using this type on my atv trailers for years. they will hold just fine if you screw them on with a self drilling sheet metal screw with big threads. just make sure you use a least a 1/4 shank screw. the ones i use are 3/8 heads and drill bit ends. just make sure when you mount them the pull will be to the side and not straight up.

http://www.ebay.com/itm/20-1-4-ROPE...item483806b6fe&vxp=mtr#ht_1518wt_670