The two megas I have going right now are V1. I also have the exact same Tron T in use and have found it to be an excellent tank. Just about impossible to find now, but there was a site or two practically giving them away last year. I got one but wish I had loaded up (I think they were $2 or $3 each). I do have a jillion megas of every variety, so I'm not hurting.
The V1 with the large slotted window is also something used here.
If you have the v2 version as well ever notice the V1 chimney is not fitted with any gasket that would meet the top of the clr like the v2 has.