I love the fact that the standard Corpus loadout is near-useless against Bursas. I hope they do this on all high-level missions, to force players to develop more balanced loadouts, and to force cells to coordinate better. It's great seeing four Tenno with Ice and Electricity only get annihilated by Bursas.
That said, the Bursa is hard to beat, particularly when you get multiple ones. But that's part of the challenge.