Anyone try Witness magazine spacers??

[Intercooler]

   For the Compact type pistols with 10-12 round mags? I'm wondering if this little addition will allow using the good 14 round K10's?

http://eaacorp.com/gun_accessories/index.php/parts/tanfolio/witness/witness-accessories/poly-mag-rubber-spacer-101446.html

http://thefiringline.com/forums/showthread.php?t=265910

I think for no more than they cost it would be worth it to sacrifice one or two experimenting.