Something we'll be focusing on in the next release cycle is much better export and import to/from other formats. We already have pretty good HAR support, and that's going to get much better soon. I don't know if the SAZ format is well-documented... but Fiddler is an excellent tool and we'd like to be able to work alongside it. I'd certainly merge SAZ support if, say, I woke up tomorrow morning to a PR implementing it.