I would question that assertion to be honest, Dan (but not because I want an argument about it ).

Other than Mato's operation in Canada, and small time guys like Phil who found out about them because they were into the hobby already, who stocks the Sherman in North America? Certainly not the big online toy sellers that Google links to like Raidentech, etc.
The same is true for the UK, only Tankzone out of Googles top 10 links have them - and its a good 50 pounds more than the equivalent spec HL, so he's not going to shift too many to the casual buyer...

From what I can see, Mato really shot themselves in the foot by not having this made by Heng Long under their brand and sold thru their channels - we are still going to buy our tanks thru our favourite retailers because of the service they offer so Mato aren't going to loose too much themselves, but by not selling a product that the 'pile 'em high and sell 'em cheap' crowd (who can shift them by the container load) as well they have lost a lot of 'toy' sales that would have paid off the investment much faster.