forbin404, thanks for the faith, but I have yet to do an MDX axle. That said, I've done plenty of others, and they are pretty much the same in the basics. I just had my son's Subaru axle out yesterday - took about 30-45 minutes (it took a little longer when I had to pull a pull a preload adjuster out to replace a seal). I assume the inside joint on the MDX axle is like the one on the Subaru (and my old Volvo), with three donut-shaped rollers riding on a three-pronged carrier. If so, you'd need to cut off the old boot (to save time) and then pop the inner joint apart (by prying, most likely). Then, clean and repack the bearing with synthetic grease, slide on the new boot, line up the carrier and give it a good thump with a soft mallet - or do what I did (after accidentally pulling my son's Subie axle apart when removing it), and stand it up on end and drop it onto the inner shaft (the weight of the rest of the shaft should pop the rollers through the little indents into their channels).
You can buy two different types of bands. The "best" is flat, circles the boot twice and requires a special tool to pull the band into tension tight and then it cuts off the excess and folds it over to keep the tension on (that's the type the original boot had). The other type is the one most home mechanics will use - it's got lots of holes (looks a little like a really long hose clamp). You just squeeze it around the boot and push down the "hook end" so that it grabs the "tightest holes" it can - then you just give a squeeze to the protruding bit with a pair of side cutters to squeeze it tight. I put one of those on my son's car yesterday, and it worked just fine - I wouldn't expect to ever have trouble with it (unlike the nylon zip tie the "professional mechanic" put on previously).
That's all fine as long as the CV axle isn't damaged from running too long with too little grease, or contaminated grease. If that's happened (or if there's any doubt) a new axle will save you time and energy - just slap it in and you're off to the races. There are a lot of youtube videos on the subject - the biggest trick is disconnecting the hub enough to get enough movement to allow sliding the axle stub out of the hub - and then getting it reconnected (normally, that means disconnecting a ball joint). Not rocket sciences, but you'll want to have a floor jack and something to pry with for most cars (again, I've never done an MDX, and hope to keep it that way). ;-)