I’ve had the 3t for a couple of years until the 6t came out and I’m still using that to this day. I’ve been happy with both of them, the 6t still works well and although e.g. the camera isn’t the greatest I have no intention of getting another phone until this one is completely dead.
That said, I wouldn’t buy a newer models since the pricing policy and the move away from their former principles made them a mediocre phone amongst many and I would definitely get a Pixel next if I had to.