if you don't inbreed you won't get the best results.All animals produced as a variety be it dogs,cats ,budgies cows etc have been inbred extensively.If they hadn't they would still resemble their original wild cousins.Mice can be inbred for many generations without problem.If and when a problem occurs then its easy enough to outcross to new blood.If you don't do a bit of inbreeding,as a hobbyist breeder you are likely to end up with a lot of heavily marked brokens and dull brown mice.Unless you want to show though you won't have to do it all the time.If you show its a must.
