Personally, I find it funny that the B'rel-R got made into a Fleet variant.. making all the other Fleet Varients pretty much even more Obsolete. Why bother with any of the other BoPs when you can just wait to Tier 5 (Or find a KDF fleet at Tier 5) And get one that way.
Because the Fleet B'rel, like the C-store variant, is much better used as a Torpedo Platform that is very hard to pin down and kill.
That and I prefer my Fleet Hoh'sus with 4 Tac consoles
However, correct me if I'm wrong, but can you use Science Abilities while using the B'rel's Enhanced Battle Cloak?