On mine, it took me a Saturday afternoon to do the filler and sanding, and another evening to cut the key slots and visor. Not labor intensive at all. I do wish I'd taken the time to reinforce the inside with fiberglass. The resin used on the SgtFang + the age of the helmet just seems slightly brittle compared to say, Asok's cold cast resin bucket, which seems bulletproof by comparison.
Anyway, you can't beat that price, and it's a great bucket to experiment on, adding more scratches/cuts to the surface before painting.