I purchased a "suspension trainer" from http://www.fitnessanywhere.com
a few months ago, and figured I'd share my impressions now that I've had some time to get a feel for it.
Let me say first-off that I have not done any traditional weight/gym training for years. I've tried to balance cardio, full-range bodyweight exercise (pull-ups, wall-squats, dips, etc), plyometric, and isometric exercies for over-all function rather than specific strength goals. This takes a lot of work, obviously, to design a do-able program within my daily environment.
So a few months ago, I heard about the TRX system from someone else who used it on the road while traveling for work. I ponied up the (considerable, IMHO) investment of $200 to have one shipped to me along with a couple of their exercise program dvd's. When I opened the package, I was not disappointed in the unit itself; it's very well made, the handles are comfortable, and as advertised, it attaches everywhere. The dvd's were, well, kind of blah...I watched them once, but to be honest, there's so much material about this system available online that they ended up being completely redundant. My personal recommendation would be to buy just the basic unit if interested. They do have a flexibility program that is actually pretty good that I use sometimes verbatim; the stretches for the upper/mid back feel fantastic!
Using the trainer has been easy. However, I use it with my 13yo, who does have some trouble coordinating some of the movements. I won't lie: it takes pretty good balance, coordination, and focus to successfully do some of the more advanced exercises. It probably does not apply to this group, but I'd also suggest that anyone who isn't sure of their core strength take it extremely easy at first, as it seems like there's a high risk of back strain/injury for someone who can't stabilize their core well enough.
Here's the best part, especially for folks who do what we do: every exercise you do, and I mean every exercise, engages your core, as well as ancillary muscles that you might not know you have until a couple of days after using it the first time.
I have improved my core strength and flexibility *tremendously* in the past few months doing these workouts. If I sound a little like a raving fan, I am. I've had a lot of soft-tissue injuries that have traditionally caused me a lot of discomfort during/after certain activities that are now healing fully, especially my right rotator cuff and my knees. The difference has been amazing.
If anyone else has one, I'd love to hear what exercises you do to help with your martial arts conditioning. And if anyone checks it out and digs it, let me know!