I'm not a huge fan of this card. It's cheap costing only 1. However, ally has to be defeated through consequential damage, cannot bring the ally back on the same turn it was defeated, have to be in alter-ego when playing the ally again and the ally comes into play exhausted, is too restrictive. It always feels so clunky. Make the Call, Regroup and Rapid Response seem more flexible.
Though Med Lab is multi-use, which is its strength compared to the aforementioned three, but it also has restrictions on how the ally was defeated and bringing the ally back into play is clumsier. And I suppose there is the second benefit that (as far as I understand) ally effects that trigger when playing it from hand also trigger when playing it from Med Lab.