drb, I’m not quite sure if this is what you mean, but It shouldn’t make any difference whether WLE9 is obtained as an Upgrade or “full” Elements Version on the page you cite, all of MrSoundMan’s points would still apply. Either way they shouldn’t be any different, or overwrite or delete your WLE 8 unless you tell it to.
MrSoundman has already covered all of this, but to add to what’s been said::
If you buy the WLE9 upgrade, you could have 4 different versions of Wavelab LE installed simultaneously, if you take care to install them to different named folders, and not overwrite one of your previous installs. You could have:
WLE 8 - 32bit
WLE 8 - 64bit
WLE 9 - 32bit
WLE 9 - 64bit
all installed, and you could open and close each version as you like to try them.
It might get a little hairy on uninstall if there aren’t 4 separate uninstallers listed in Windows “uninstall a program” control panel, but I would hope there would be 4 separate uninstallers. (edit: it looks like there are).
After install you could open the WLE 9 64bit version to see if it supports all the plugins you want to use. And if not, maybe try to obtain 64bit versions of those plugins. That is, if you want to use the 64bit version of Wavelab. The only reason I switched one computer here to Wavelab 64 bit was because I needed Wavelab to access more than 4GB of RAM for times when using a lot of instances of big plugins. And only the 64 bit version of Wavelab can do that.
But if you’re not running out of computer memory the way you work now, you might just want to stick with the 32 bit version. The quality should be the same as the 64 bit version.