And the reason no one is talking about them is they are very outdated technology, one of Flir's first offerings, and long eclipsed by newer equipment by Flir and other manufacturers.
No one is talking about them further because very few people use them any more because there are so many more better less expensive items available that have proven themselves to work better.
The T50 performs about equally with a PTS233, under performs a PTS536, and a used T50 costs more than both units combined new, and a used T50 has no warranty and the 233, 536, and 736 cost less, perform better, and have warranties.
There are a lot of knowledgeable posts on Snipershide about thermals, much to learn, and worth spending time reading. The lack of T50 information should be significant evidence not to buy one.
Wigwamitus has stated the truth about the PVS14 eyepiece thermal units, and their non Clip On capabilities and there are several threads here full of information worth reading.
Snipershide has the most information you can find in one place on using thermals. Please search and read more b4 wasting your $ on a T50.
Best to you.
vr