I need to replace a Terra TRT250D (it's failed for the 5th time). The
only transponder that might fit into the Terra's rectangular cutout in
my crowded panel (if I do some horizontal filling) is the Trig TT21.
The Trig's specifications look good and it has an attractive price,
but it's brand new on the market.

Does anyone have any experience or thoughts about the Trig TT21
transponder that they'd care to share?

-John