Thank you everyone very informative posts, as they have been very helpful. I figured a 400nm jaunt was a bit of a stretch for a helicopter (although I tried to convince myself otherwise), but it is good to hear it from the experienced members on this forum. I did figure that a fuel stop would pretty much be mandatory with almost any helicopter, even for the 109. By the way, the ground level in Montana where we would be operating at is around 4,500ft, and that is in the valleys.
We have tossed around the idea of a plane for the cross country portion as well, and it does seem this really is the best way to go. I will certainly suggest we look further into this, but ultimately I'm not the one to be making the final decision
In anycase, your suggestions and comments have given me something to think about, and it seems there are many possibilities available (although it looks like I can stop dreaming about the 109). Even fractional ownership in a fixed wing might be another option.
If nothing else, I think I will continue to build hours in a helicopter and perhaps go for my CPL and/or IFR rating, while my brother continue to build fixed wing time and additional ratings. That will leave us better prepared for the future and open to more options.
Thanks again everyone...I've been searching for an online forum of knowledgeable aviators and it looks like I've found it!