I currently have a 4x5 Sinar F that I have used for about 2 years now. It was cheap and I can make it work but its not really ideal. I would prefer a field camera over a rail since I travel quite a bit. The biggest feature I need on the next camera is a brighter easier to focus ground glass. The sinar f I was using with a rather nice 135mm rodenstock apo-s was a challenge. Not sure if its the fault of the lens or ground glass but even at 5.6 it vignettes very hard and its hard to focus (even with a 10x loupe). I got to try an 8x10 master view and man that was easy to focus and see everything. Do I need to go up to a linhof technika or can I get a clean speed speed graffix and replace the ground glass? Hoping to spend around $1400, maybe more if I have too. Thoughts?