I got a pair of Bontrager T1s, 27" x 1 1/8", during the pandemic when they were the only 27" tires I could find after canvassing local bike shops all over greater Boston. I rode them on a vintage Bridgestone road bike, for recreation and with panniers of groceries, on a mix of mostly good paved roads and unpaved paths, in both dry and rainy weather.

I road them at 100 PSI; I weigh about 170 lbs.

My overall impression is that the Bontrager T1s are pretty good mid-range tires, better than CKS or Kenda, I would choose Continental Ultrasports (if they are still available; it looks like Ultrasports may have been discontinued in 27" sizes) over Bontrager T1s for similar uses at a similar price.

Good: Good traction on a range of surfaces, wet or dry, including under a heavy load. (Particularly good wet traction, and decent on fine crushed rock or smooth dirt, although I wouldn't choose them for coarse gravel.) Smooth ride. Available in 27" x 1", 27" x 1 1/8", and 27" x 1 1/4" sizes.

Bad: Poor road feel, Feel somehow "dead", as though they are heavier than they are. Much slower if even slightly underinflated.

I was riding on roads without a lot of glass or debris, and not in goathead country, so I can't judge flat resistance.