Starting on large format, I've been astounded by the prices of sheet film in shops. As they only come in either 10 sheets or 20 sheets per box, it would probably work out cheaper to buy and split a bulk order between myself and others.

For colour I won't use anything other than Fujichrome (Velvia, Provia) - I assume these are stable in the 5x4 camp.

What about black and white? Reading the forum posts on Ilford, I wonder if it's a safe bet to try mastering 5x4s on a film brand which is a bit unsteady. What else do people use here? I'm curious about Agfa Scala in sheets (wow!!) and I also heard of some other brands - Marco film. Are these worth a run? I'll be developing in a 10x8 processor by hand and my regular chemicals are HC110 and rodinal.