Hello All

I have a very broad question, which I presume a number of you have answered in the past.

To begin with, I have been shooting with my Mamiya RZ for around 3 years. Over the years I have mainly shot documentary style projects, a lot of portraiture work, and I have found that with travelling and working away from home the RZ has been very practical. Now I have been shooting a lot more landscape based work on my RZ and I have become disappointed with my results, and Im finding it a bit of a compromise.

Ideally I would like to invest in a 4x5 camera, but I am really concerned with the cost of film. I have seen 10 sheets of Kodak Portr go for £45 which is probably too much for me. So to cut to the chase Im after some advice about upgrading to a large format camera that I can buy a 6x7/6x9 back for. I thought to myself I would see what is available online and research from there but I am struggling to find much for sale in the UK.

Is there many benefits changing from a RZ to something like a Horseman VH-R if I am still going to shoot 120?
Any advice on cameras/film will be much appreciated. Thanks in advance.