I suppose (and I'm speaking in complete absence of personal experience here) if one was after a really big AFOV one could give the WO UWAN 28 a shot, which Tom Trusock characterises as a close second to the Naglers. It is just as big and heavy as the 31T5 but can be had from WO directly for US$359 shipped at the moment.
Just saying…
Cheers
Steffen.