Hey George! Yes it's worth for sure! I've bought:
2 square meters of 'K-flex Self-adhesive Insulation Foam Sheet' 10mm thickness, 20 €
2 square meters of similar foam sheet(not Self-adhesive) 3mm, 20 €
Aluminium foil tape, 7 €
Rubber tape, width 5cm, 2 mm thick, 8 meters, 15 €
Spray...