Hi George -
I have bought several Frontier Models. First off, they are not in the same league as Modelhaus of Promolite - you will likely have to do some minor to major reworking of components depending upon your standards and the particular kit at hand. These are NOT "shake 'n bake" models!! Having that said, I have never encountered anything that was unbuildable, and the subject matter of their kits simply cannot be found elsewhere(one of their newest offerings is a 1948 Packard Henney Hearse/Ambulance combination!!).