I will be getting a tune soon and obviously we are in winter blend gas right now.

From doing some research on google it seems that winter blend is the crappier of the 2.
I'm assuming it would be safer to tune on this so when summer blend comes around it's not on the ragged edge

I also wanted to know if it would be best to tune with passengers in the car to promote load and possibly taking steep uphills @ times to verify a safe tune

any clarification or info would be great

 

Bump for any info from tuners or informed people

 

Most of the time the summer blend when it comes back around will run a little richer. but you should be fine in the summer.

 

If its tuned properly it won't matter much since the ECU has built in safe guards for lower octane fuel. Now if someone tunes it who overrides that then you have an issue.