RE: For everyone voting I agree with everything you just wrote, and have averaged down myself considerably since the deals we're announced.
Everything under 15.5 is a break even trade at worst from here in my opinion. I'm actually the most confidant I ever have been in buying FIU under that price. However, barring any news, be careful above that, as you'll have the short term merger arbitrage flippers selling into any bids above that price, and it won't long stay over that until they are all filled, which will take decent volume. So if you're adding have patience and for now let them push it into you unless you really want the fill.