I watched 18 and 19 on G4. They aired both on two consecutive nights, IIRC.
20 was spectacularly, horrendously, and utterly catastrophically spoiled.
I watched 21 on G4.
22 was supposed to be my first live tournament, but I had a conflict so I watched a recording a few days later.
I've watched 23-29 live. I got very spoiled with 23-25 being so back-to-back (exactly 6 months between 23 and 25), plus, 23 had a Final Stage with Nagano, 24 was a Kanzenseiha, and 25 was the big renewal.