Which breed of duck is best?

I have a Khaki, an Appleyard, a Cayuga and a Blue Swedish. All are laying really really will with each taking just the one day off a week to rest 

The Appleyard is my favourite of the girls, but that is because she has a dodgy pelvis and waddles funny and is a bit slower than the rest  Although skitty I also like my Khaki's personality as she can be quite a madame at times. The Blue Swedish and Cayuga girls are both fairly calm and pretty to look at.

The Khaki has certainly laid no greater number of eggs than the other girls, although she did start a little younger (20 weeks as opposed to around 24 weeks) than the others and the Cayuga was the slowest starter and took 4 weeks from laying her first egg to laying her second, but is now regular.

My two drakes are Aylesbury and they are my favourite, although obviously I can't comment on eggs as they don't lay! They are so friendly and love a fuss and they are what made me fall in love with ducks more than chickens.

I'm not sure how the ducks managed it today as they have all laid twice - 4 eggs this morning and 4 again at bed time! I know that none were from yesterday as I collected an additional 2 before I locked them up in bed so the house was empty of eggs (so 6 eggs from 4 yesterday as well) As wonderful as the ducklings Kate gave me are (both fully quacking and no cheeping any more) I know they can't have laid them so the girls are on egg overdrive!

I personally would pick the breed on how friendly they are and which you find most attractive (maybe even for egg colour such as the Cayuga or Runners) and rely on good husbandry and lots of tlc giving you lots of eggs regardless of breed.