I think I have to agree with all those who have expressed concerns about the welding aspect of it. There really aren't all that many folks out there with the proper skill set and equipment to do a quality job of assembly. Does your company really want to stake your reputation on the welding and finishing skills of the average guy with a crackerbox in the garage?
Now the bolt together idea has merit, especially if you could come up with a design that featured interior fasteners, so that nothing was exposed. I do think that I might want to market them as secure gun cabinets rather than safes, again, because you're reliant on the assembly skills of the end user.