I was seriously considering them in place of 4 GC, but the physical height and weight conflicted with where I could mount them, so the GC won out. Had I had the height with enough room to handle them to get them in and out I'd have gone for them in a heartbeat.
But I also have 12 years on one set of T-125's in one trailer that sees close around 25 discharges to well under 50 percent each year and they are still going strong. And the 4 GC in my 2010 see similar use and are still going strong. True deep discharge batteries will take a huge amount of charge discharge cycles if properly cared for and the T-1275 falls in that category as well.
The T-1275 has a very very distinct advantage for high current loads. To run the microwave at 900W on my trailer I really need 4 GC if I want the microwave to run at below around 80 percent SOC.
