I'm still getting caught up on the extra expense of dealing with 4x5 (and have yet to produce my first successful negatives, let alone a print... grrr). I'm betting you're probably right, and as such I should probably limit my chance of exposure to such temptation until my checkbook is ready for the expense of jumping to yet another format.
Makes me wish I lived in N.C. I would have you up and running in about a day. It's all about controlling process. Understanding handling film, metering, development, printing. 4x5 is no more expensive than 135. You shoot less, you get more. You stop being a picture taker and you become a PHOTOGRAPHER.
After I got done looking at all of the extra stuff I'd have to buy to treat sheet film the way I've always treated roll film, I let it go and went to using trays last night. The first four shots I took with my Graflex Crown Graphic were lovingly bathed by hand in trays in my bathtub while I sat on the floor. I used the DigitalTruth Massive Dev Chart app on my iPhone as a timer (just need to find a better way to contain the ambient light from the screen while still seeing the timer).
I need to refine the process a little bit but the negatives look good.
Next up? Finding a portable enlarger & learning to print!