I had (yes, sensitive contributor!) Previously often skin irritation, so they are now pretty much gone. When I had to wait even two weeks on new cartridges, the skin problem was in this period again, despite intensive manual cleaning.
My conclusion: With regular cleaning by the cartridges I go much better in person!
My experience (as well as Mr. Sackbauer confirmed below) has shown that an intensive cleaning of the razor a week with the cartridge is sometimes quite sufficient. Otherwise halt after every shave remove and tap the shaving foil and blow out. Before I brush cartridge use the shaver thoroughly, so the cartridge lasts me three months and longer. Is it in the bathroom warm (summer or heating), then evaporate more of the cleaning liquid and the cartridge must be changed more.
Granted, the cartridges are not really cheap and there is no alternative providers, but with a collective order together with friends and colleagues at a eBay seller can save quite a bit!
Overall, a pleasant gimmick, that I reluctantly renounce in my daily life!