I went from a 5050 in an Ike housing to a DSLR early this year. It's a hard choice, and mine was a smaller step than yours (just a Nikon D70). I looked at Nexus, Aquatica and Subal housings, with all imaginable port configurations.
Long story short, I wound up right back at Ikelite. It might not look quite as sexy as the metal housings, but it had everything I needed, including excellent TTL, and the price was as good as it gets. It still wasn't cheap for me, I can't afford to throw money around, but when I considered all my lens options, and the ports I would need, the Ike fulfilled every category.
And if the worst happens, and it begins to flood, at least I can see it, and get a fighting chance.
Six months on, I think it was still the right choice. Good luck with whatever you choose, I believe it's a very nice camera (although with full frame, your lens choice will make a big difference).