Your choice will depend of what kind of pictures you will take.
In the studio and for close-up's a monorail has the advantage: the lens-object distance determines the size of the object in the photo, focussing is done with the back-standard.
If you just want to photograph landscapes and architecture a camera like the Chamonix is great.

Look for a camera that has interchangable bellows: most of the mono-rails have aswell as the Chamonix (on my wishlist).
Once you want to use wide-angle lenses these bag-bellows are a blessing, I hardly use the standard bellows on my Sinar P2.

I actualy did a lot of architecture with the P2, never went hiking with it though.......: too heavy for that.

Good luck and welcome to the club,