I avoid leaving something behind in the graduated cylinder by mixing directly in the storage container. Graduates are only used for mixing final solutions from stock.
Will my stock solution volume be exact?
No, usually not. Pyrocat HD will be, because I mix it on a balance so I always know the total weight. More concentrated (or larger volume) solutions won't be, but anything closer than +/- 5% probably gives less variability than the differences between film batches.