They're fine, but they did recently put an order minimum of $299+.
SD Bullion's got a bit of a delay on their order processing (They do lock your purchase price though regardless of what the market does before they finalize and ship the product).
They don't have a minimum purhcase order though, and their asking price is a bit inflated given the day-to-day price of silver per ounce. (Varies, but around $31.00-$34.00 per oz) While both options aren't exactly great, they're both trying to hedge their bets on the volitility of the market, either buy in bulk and spend more than you might have readily available to you, or pay a higher premium to ensure you can get a few more ounces in your stash.