I believe it's a 2.5 liter kit. I think they say 3-5 rolls per 250ml solution, but their math is for 5 rolls per 250ml, hence 2.5 liters does 50 rolls. If you look on the Maco Direct website (http://www.macodirect.de/digibaseİ-m...1°-p-2340.html), it seems to imply that the math is for 6 rolls at ISO 100, 5 at ISO 400.
I've only tried 4 rolls in a given 250ml, the first three were fine, the fourth was not, but I messed up on that, it wasn't the chemicals. They were about 2 months old, though, but I'm certain it was my fault.