Like I hoped, after a few months of hunting, I was finally able to find a really good deal on a road bike, in the winter. With the money saved, I was also able to buy a smart trainer to use with Zwift.
I need a spare cassette for the trainer. My current setup that came with the bike is 105 CS-R7000, 11-30T I'm thinking of getting a second cassette with a different range - I can see that they generally all start at 11 teeth and can even go up to 34T, but actually I'm thinking of getting 11-28 instead as where I live is pretty flat and i don't expect to use the 30T at all.
Should I get a different size cassette? Which one should I use on the trainer (given that Zwift has Alpe d'Huez etc) and which one should I keep for my road use? Is there any point in getting Ultegra (my bike is 105) and I clearly don't care for the weight on the trainer, but I've heard reports that Ultegra is more durable?