For most of us, yes. I do have 3 L3i mag extensions.
Regarding the L3i extensions: I would buy an extra mag or two before buying them again. They were a bit of a fight to get them installed. I put one on a steel CZ 10 round mag and two on CZ 10 round polymer mags. I could never get more than 10 rounds in the steel mag, with or without the extension, something was catching and it just would not work, so I put it on another Polymer mag. While they feed flawlessly, they are always a fight to get rounds 11-13 in, and usually require a lot of banging, tapping, and fiddly-farting around to get them filled to capacity. I have had them since last year, and they are getting gradually better, but I do wish I just grabbed two more mags instead.
