There is a phrase I have heard quite a bit recently dealing with people that are leaving the department for promotions, etc. When a person leaves, it is good for them, but bad for us.
It is good for them because they will be pursuing a new opportunity, but not so good for the department since they will have to be replaced, and others will have to pick up the slack until someone else can be hired and get up to speed.
Is there a word that means that a deal is good for one party, but not necessarily the other?