Perfect attachment in every way from design to cardio workout. Up until this purchase, it was always a challenge to get enough cardio in safely, without hurting myself, due to an old back injury. I can now exercise regularly without any pain!
Got mine a couple of days ago (to use with my XLS). It's a great workout for a simple device - but I do have two gripes:
#1 - the computer takes "C" sized batteries. Nothing uses Cs any more. I had to make a trip to the store to buy batteries, because the Cs are the only size I don't use for anything else.
#2 - The support leg needs to be adjustable for distance out/in from the end of the Total Gym platform. I am a tall guy (6'5") and with the slider bench at the bottom of the frame, my knees are bent to the point that pedaling is uncomfortable / difficult. I remedied the problem by placing a length of a 2x6 across the slide stops on the frame. This moved up the bench a few inches, making a much more comfortable position for my long legs. It wasn't a hard modification, but it would nice if I could adjust the attachment further away... or if the slider board had a series of holes where it could be pinned up a little higher on the frame rails when using the bike.
I originally bought the smaller, less-expensive model of this attachment. However, I quickly learned that I was going to need the features offered by this model—specifically the timer and the resistance level adjustment. That smaller model doesn't offer as many levels of resistance, and none of the levels that are available provide very much resistance.
This model fulfils both requirements. Being able to set the timer and not worry so much about the clock is a huge improvement. As for resistance levels, this version offers 16, with real resistance at the upper end. I expect to be getting plenty of use out of this attachment.
However, there is room for improvement.
First, I don't detect much difference in resistance from levels 1–7. This means that this model has at best only about half the promised levels of useful resistance. (It's possible my legs are in better shape than I think, but I've been hunkering down for most of the last several months like most other folks, so that doesn't seem likely.)
Second, the user manual could do a better job of explaining the parts of the display. Presumably the distance indicates miles, and the speed indicates miles per hour—but the manual does not specify this and, third, there are no markings on the display itself.
Fourth, an on/off button on the display panel would be useful. Yes, it turns off by itself eventually, but there doesn't appear to be an option for setting the automatic shut-off time; the ability to shut it off sooner would help prolong battery life.
Still, overall this model is worth the extra money.