Personally I put my singles in old boxes. I mix and match, whatever will fit in the box. I have several size boxes in there, for churchills, robusto's, etc.... I mix brands- no problem. I personally do not keep cigars in baggies- but I asked a similiar question- and the consesus was to either open the end of the baggie or remove the cigar from the baggie to properly age and store the cigar.
Hope this helps. GOOD LUCK.