We have a Tundra 8, stove and ground sheet from the group buy. It has had a lot of use and a LOT of rain this summer.
Some observations...
Weatherproofing definitely helps. Best case is to let it dry completely after a big downpour, and repeat! We had leaks first couple of times, nothing since. One night the rain was so heavy and persistent I was sure we'd get wet, not a drop

Get some webbing loops (stronger than eyes) added to each point on the ground sheet. With a taught ground sheet, if you peg the tent loops tight up against the edge, the tent goes up perfectly every time, and the skirt has room to do its work as a weather barrier, particularly if the pitch is not completely flat.
The bit of the ground sheet directly beneath the entrance catches water and muck in bad weather and is superfluous. I intend to remove a section.
The ground sheet is not compatible with the stove. If you want ground cover, on wet grass for example, with the stove, you need smaller ground sheets to go round the stove, or I guess remove a central section of the ground sheet, but that seems overkill?
Agree about the guys. They need a good stretch before pitching first time. They tend to twist. I am gradually replacing mine.
Plenty of room but for heavy family use (we are 5) a tarp for cooking and eating in bad weather is a good idea!
Lots of people like tipis

They come up and ask about the tent in public camp sites. I tell them if they like the aesthetics of a tipi they must be a bushcrafter and should visit here

All in all Bison are excellent value tents that work really well!
Chris