Is this the one you are talking about?
Tech Rod
I see about 7-8 exercises right off the top of my head that you could do. About 3 for the back, 1 for biceps, 1 for triceps, 1 for legs, 1 for the chest, and possibly a few more. So its up to you. The machine may say you can do more, I dunno, I just don't see it.
Here's another machine you may want to look at as well though. It says it has over 50 exercises. I'm not so sure about that either. They probably do, I just don't know how many are necessary.

So its your choice. But if you don't want to go to the gym, and are just looking to kind of tone, and maybe get a bit more strength, then either one would be fine I guess.
That Weider one (the picture says its a Crossbow) has a rowing exercise though, which may be good for blood pressure. You'd have to check with your doctor on that though. It doesn't have the leg extension like the other one, but you could probably do squats with it.
Hope that helps a bit. :clank: