Are you heading to trial expecting to use deposition testimony from other cases? If so, are you sure the evidentiary issues will be resolved in your favor? What if the trial judge sustains an objection to your use of prior deposition testimony--testimony you were depending on to prove your case?
You can avoid this problem by working out a stipulation with your opposing counsel ahead of time. Here's a stipulation that's worked for me in a series of mass-tort cases:
The parties to this action, by and through their counsel, stipulate and agree that the prior deposition testimony of Defendants or their employees from any state court [particular type of mass tort] action may be used in the trial of this matter for any purpose, as long as such deposition testimony is otherwise admissible under the rules of evidence that would apply if the deponent were testifying live in Court.
Since I represented the plaintiff in the cases where I used this stipulation, I was the only party who wanted to use prior deposition testimony. Why did the defendant agree? The defendant got something too: the stipulation made some additional depositions of its employees unnecessary, since those employees had already testified on the same facts and issues.