Actually they dynoed the Sirio CL7B with the JP series on them,
JP-4 was the best all round, then the next best was the JP-3 almost made 2hp 1.87 if I remember right.
Run times on the Sirio are sick to begin with, 10 to 13 mins on a tank.
With the Big Boy I was getting around 11 - 12 mins, with the JP-3 i'm getting 10 to 11 mins.
I put the Big Boy on a GO R-spec. Works well, but the run time was only 9 mins
Here are some photos of my Sirio CL7B the 09 edition.
I'm pretty sure that Extech is exactly the same as the CL7B, I haven't seen the guts of the extech yet.
