Abena M4's are very good for messing, in fact I'm just about to mess mine as we speak. The criteria for a good diaper for messing is a. good standing leakguards and b.thick and preferably plastic backed. So Molicares are good, M4's are good, ABU Space, Bambino Teddy, Classico or Bellissimo, DC Amor/Idyl, Snuggies Waddler, etc. any of those would be good.
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If you plan on staying in your messy diaper for a long time, be sure that you're alone so you don't bother anyone else with the smell and really be sure to use plenty of baby powder to minimize your chances of a diaper rash. Even then I would only recommend wearing your messy diaper for 30 minutes max after you mess.