something tending to have both good and bad results or characteristics; something having a mixture of advantages and disadvantages
Owning a car is a mixed bag. It is convenient, but also costly.
If you describe a situation or a group of things or people as a mixed bag, you mean that it contains some good items, features, or people and some bad ones. Research on athletes and ordinary human subjects has yielded a mixed bag of results This autumn's collections are a very mixed bag. A collection of dissimilar things; an assortment