BX-1's are OK to sell on eBay and now that most of the 25's have been removed, the BX-1's have gone way up in average to middle $20's each. I got some at Walmart last year for $15.88.
Is there actually a place / situation / competition or some such where you would need or be required to use a BX-1? I mean where you could not use a standard 10 round mag with just one round loaded?