If the current CV's are originals and you decide it's time to replace both of them (the one with the ripped boot is obviously ready for replacement), make sure to compare the original sensor rings to the sensor rings on the replacement CV's for overall condition.

The last time I replaced the CV's on my FWD car, I noticed that the ABS sensor rings on the new CV's weren't near the quality of the originals (not to mention that a lot of the individual teeth were smashed, dented, and generally irregular), so I had both sets of rings pressed off then had the originals pressed onto the newer CV axles thinking that they would at least provide a better signal trace for the pickups.

You'll probably hear different trains of thought about whether it's better to replace both CV's (front left and front right) at the same time, or, to take an if-it's-not-broke-don't-fix-it approach and just replace the obviously broken one, but unless you can actually find an OEM replacement, I usually try to stick with the current OEM stuff as long as it's still working since it usually seems to be better made.