Releases like BOBW and Redemption serve a purpose that is lost on episodes like Unification - it combines episodes that would be separated by different discs/seasons/dates. It provides a temporary selling point by allowing fans to resolve the cliffhanger right away.
I really disliked cramming the two episodes together. I watched The Best of Both Worlds
last night and it just didn't "feel" right. No great Rod Jones musical cue at the end, no "Last time on..." at the beginning of part two.
Glad I told my daughter she could have it after I watch the episode and the special features. It won't be taking up valuable real estate on my Blu-ray shelf.