I looked at one that Mike Partridge had at Barber's Vintage meet. The metal isn't smooth and will require a fair amount of filler and the filler neck is different, but for a modified street bike this would be a good alternative to a 'glass tank. From 20 feet away it would be difficult to pick up on the filler neck difference.
I would still rather pick up a dented stock steel tank and send it to a metal wizard like Ross Thompson. You might have a little more invested, but it would be right.
One of our guys bought one and said it needed $200 in body work before it was ready for paint. Original dented rusty tanks have been selling for about $300 on fleabay, but I'm sure the body work would cost a lot more than $200.
BTW, you can buy the Pakistan tanks from most Norton parts dealers, not just the ebay merchant.
If you're building a bike for show it wouldn't be the best choice as I'm sure the judges would notice the differences and dock points. Might be a good choice for a rider though.
Well I got mine and I am happy with it. Sent it out for paint will have some Pictures later. It had the dents forward and backwards to accommodate the hinged cap. All it seems to lack is the slight indent around the sides of the neck. Way better than a glass tank. 450.00 plus shipping. From a dealer.