Given the move to Washington, run your maf unless you are maxing it (doubt it with your boost level).

Choosing SD in that climate will just mean you need a very very good custom tune with a lot of time spent in the details adjusting for the season change -- or multiple tunes that you change out according to the weather (e.g. a winter tune, a summer tune, etc). Temp will have an impact with the range you are talking about but the humidity changes will have more impact.

 

Since you are not tuning it yourself and your "key factors will be the reliability and dependable drive-ability of the truck on a year round basis" I would think you would be better off keeping the MAF.

If you ever consider taking over the tuning duties, and/or your future modifications dictate it, then SD becomes a much more viable and maybe required option.

Once you start to mod a tune is never really truly finished.

 

Yes, I understand what you mean by it never being finished. I have read a lot about tuning, and plan to get into it. just right now on this project it isn't the right time. I appreciate the advice.