I'm not a young pup anymore and the situp, pushup, highspeed bike thing is out of the question. That's for younger, in-shape people. I have an irrepairable hernia that would not work with this kind of a workout.
I also need something that I can fold up and put in a very small coat closet when not in use. So, for me anyway. I think what I picked out is probably the best choice.
I've looked over the page you listed, and I still haven't been able to figure out what these things are. I don't see anyplace to sit, etc. I definitely don't want to have to purchase something that's non-portable, causing me to have to also purchase a bike and have this mess all sitting in my living room in front of the TV forever.
For me, there are no commercials.
Oops, my bad. Those are trainers used with your existing bike. You attach it to your bike's rear wheel, turning your own bike into a trainer. So you have a bike, it allows to repurpose your bike for indoor training use. You can adjust the resistance to make it harder/easier, in addition to using the gears on your bike.