Yes, I believe that these do get hot enough to 'bend' styrene (thermalforming) plastic, but I should caution you that they are not enough of a heat source to thermaform anything and more importantly they're not very focused for making nice straight bends.
For straight bends I have always used a 'camp' or utility lighter. One of those that has the long neck...that way you don't constantly burn your fingers on the hot metal end like you would with a regular lighter.
Just be careful and don't burn your house down. Styrene does burn...keep the lighter like 2-3 inches away from the plastic and you'll be fine.