The Heller kit is quite old Daniel.So I guess panel lines aren't engraved but are the positive ones.The Academy kit is "younger" with engreved panel lines and some options for a couple P-39 versions.But sometimes these old kits are really nice and better in dimensions and its shape as the newer ones.So I think it can be good shot.You will get your opinion when starting to assemble the kit. For me the kit is fine.