Buds does a LOT of business. When you received notification - so did perhaps 1000 other people waiting for Silvertips. Right now, at 8PM there are over 900 people logged-on and shopping at Buds. I've seen as many as 10,000 people logged-on during the day.
When I received notification about the S&W R8 becoming available I jumped on it in 2 minutes. I've received notification of other guns, not acted, and 5 minutes later they're no longer available.
It's possible 200 or 300 people all ordered Silvertips within a 5 minute period, and then - That's All Folks.
I've only bought one gun at Buds, and nothing else, so this is only my opinion.