Me too, and that is why I am asking about others' experience .
I hoped to hear the heat gun may be dropped if the foil is applied to small panels like hood, doors and so on. Or to hear there are similar products that need moderate heating or none at all.
The idea itself is brilliant, and, if applicable to model cars, takes us into a totally different corner where we will stop buying expensive airbrushes and exclusive paints, and will buy high quality knives instead.
I built it several years ago. Magnificint car, but an awful kit, both accuracy and quality wise sadly. I hope the 1/16 (Revell) and 1/20 (Do not remember) Versions, which I have not built yet, are better. However, I like your color choice. I tried to follow the instructions with a green shade which ended in a disaster. Anyway, I do not regret it since the kit is terrible, as mentioned earlier.
During a visit to the attic today I discovered that I have an Airfix/Heller 300 SL. It is a different kit than the Revell with a more detailed chassis but no open doors. I do not remember the Italeri 300 convertible, and as I said, never seen the gull wing, but somehow you feel Italeri finger prints there. It has separate front and rear clips. However, they do not affect the assembly of the kit. They can be attached before the body is mounted on the chassis. The revell kit has a primitive base plate which includes a front clip. This means it must be glued to the body in the very last step, i.e. after painting.
The kits are compared in the photos. Right, Airfix, left; Revell, and in the center, the king.