The reason 9mm and .223 are so cheap is because they are also standard NATO rounds and if you look around, there is alot of surplus ammo for sale, that contributes greatly to the low price,as far as the .17 goes the Rifle mfg's have a little money invested,and one has to keep up with the jones's so to speak which is why they are all jumping on the bandwagon, but any .17 could easily be converted back to a.22 just buy changing the bbl, and I'd also be willing to bet a .17 bbl could be punched out to a .22 so, they could easily convert back in case this flops, As I said the sucess of this cartridge depends on the price of the ammo if it goes up it dies, if it drops it may stay around, it all depends on how many of you are willing to spend $10.00 a box for rimfire ammo, I know the .17 is supposed to perform well, But, I'm not willing to spend $10.00 a box for rimfire ammo, and for what I use a .22 for, it does the job nicely, at a $1.00 a box....