1. CVs should last the life of the vehicle as long as they never run dry. Keep a close eye on your boots. I suggest you kneel in front of your VX everytime that you gas up and look underneith. If properly done, everyone will think you are praying to keep it running a little longer and will be so impressed they will start doing the same.
2. The longer you wait, the more expensive it will be. When they start making noise, they are gone and require a rebuild but that's not too bad as long as you can find someplace that will do it. Should only cost about $150 - $300 depending on how many CVs need work (remember there are 4).
3. If you do procrastinate & keep driving it, you run the danger of wearing the housing. That's when you start getting into $$$ (assuming you can find someone to do the work).
4. Be prepared to do some SERIOUS research. You'll find places that indicate they carry the parts - until you try to order them.
5. Yes, it is worth it. When you finally get behind the wheel again, it's worth all you've been through.