I've got monkey foot wet bags for when out & a bucket for at home. I do leave any wet nappies I have in the bag till I do a wash & I would say some smell does escape so I personally am sticking to my bucket that doesn't leak smells at home
I got my bucket from thebabycatalouge & find it to be bigger than the mothercare ones. Holds 2 days worth of nappies for my 2 LO's, so about 16 nappies which is the perfect wash size for my machine. Once the nappies are in the machine I just spray the bucket with anti bac & give it a wipe over with kitchen roll, easy!