I've bought from them several times over the years and have never had a complaint. They do what they say, ship within 3 days of the point the funds clear and usually ship 2 day. They waffle between Fedex and UPS for larger PM orders just to mix it up (signature required, obviously) and for smaller stuff (bought a handful of bullion bars over the summer) either just "drop and run" UPS or Fedex or sometimes, priority mail if the package value is low (probably under $100).
I can't complain. But there's always someone who will. Thats a given.
And then its not a matter whether your order was screwed up or not because it happens on occasion. What matters is how willing they are to fix the problem and how quickly they do.
But again, I'm going to emphasize that you also need silver bullion wire to hang the bullion bar on. You cannot use any other metal nor can you just use an alligator clip to hold the bar and think by keeping it out of the water you're OK. Your not. Even condensation "could" pose a leaching risk here and alligator clips are not plated with anything I'd care to get inside my body as an ion. You need to drill a hole through the bar and string a silver bullion wire through and either do as Kephra does (which requires some skill) or "twist tie" it tightly with the longer end used to hang the thing.
I would also caution you to choose a very secure wire holder for your lid. As has been pointed out, if the bullion bar "falls off" while in the cell, it will instantly win the confrontation between itself and the glass container and then the "dam bursts" and your significant other reaches for the meat cleaver for flooding her kitchen (wink).
Seriously though, that is a mess I would NOT want to have to clean up!
As has been pointed out, a single 1oz bullion bar is enough silver to make 1000 liters of 20PPM. In English measure, 1ozt silver will make about 432 gallons of 20PPM however thats not practical because you can't use it up. I figure around 300-350 gallons you'd be getting to the "not usable anymore" stage at which point you sell it for silver scrap and buy another 1ozt bullion bar. You most likely would not be able to use up even one single 1ozt bullion bar in your lifetime though.