JSON polyfill: JSON 2 or JSON 3?

Question

I need a JSON polyfill to support IE 7 and some IE 8 and IE 9 modes. Should I pick JSON 2 or JSON 3? Obviously JSON 3 is a more modern implementation, but for example a site

Answer 1

Use json2.js if you want to improve the performance of your page in IE7 (and possibly 8). I was happily using json3 for months and then I saw this question and did some research. All of the jsperf's performed 1-2x faster with json2.js in my IE7 VM.

One example:

http://jsperf.com/json-vs-jquery-json/2