can't tell what others got but bought 2 of these 13x5-6 tyres. Fakes, and both installed in just 25 minutes. I use a roll of tape to keep the rim stable and some soapy water, nothing special. As far as tire curve goes, it gets a little round, but it has pressure-reducing shoulders. It should not stay at a maximum of 30 psi. It lasts for the life of the tire and cleans your rim of rust and dirt. There will be some air leakage when you install it over loose paint and rust.