Last year I switched from Tetenal to Kodak for my C-41 and RA-4 chemistry, and liked it much better than the Tetenal. Anyway, back on Feb 20, I mixed up a quart of RA-4 and made 5 8x10 prints. Two weeks ago, I had to make 18 contact sheets, and thought I'd try the chems I mixed in Feb. Why not? If the first one's junk, just mix a new batch. They looked GREAT! Two days ago, I finished making another 18 8x10's from that chemistry! Color balance and exposure remained consistant throughout. 36 8x10's from 4 month old chemistry; I'm very impressed.