Download the trial version and then when you know you will have a lot of time to focus on it give it a thorough try.

Make sure you do a system backup FIRST just in case something unexpected happens and you need to go back without having to do a ton of work.

Vegas 9 is much more stable. Personally I would wait until Vegas 13 and probably until the near end if it's lifecycle based on the past 3 buggy releases. Unless of course you need some of the newer features for editing. The days of rock solid Vegas stability are long gone and they do not seem to have the staff to fix it.

I use Vegas 9c. It is not very stable.

Peter have you tried Vegas 9.0e?

I use 9c because it is the last version that smart renders AVCHD. I can't comment on 9e stability.

9.0e is a different code than previous 9.0* versions obviously. It will not do the things that were attempted in previous versions.

BUT, but, the most important part is that IT IS STABLE as they come. I use it 24hrs a day seven days a week on multiple machines in a network and absolutely no problems. I have more problems altogether in just keeping Windows 7 OS alive and stable on this platform. Does that tell you something?

I must see if there is a way to install 9c and 9e at the same time, so that I can edit with 9e and render with 9c.

On the same PC, just create multi-boot system with separate partitions so that you can separate the registry entries for each. Version 9 runs well on 32bit XP , so this could be your least level entry point for a multi-boot system.
Or within the same PC, have two separate bootable Harddrives - eash with an installed version of the base OS...you will usually need two licenses for the OS ... although if you have identical drives - you might get by with a clone of the partition of one OS/drive to the second drive. Make a third drive the source and destination of project files.

DO NOT upgrade!!!! Idid and it is a WASTE OF MONEY!
Most of the "new" features in 12 you have to TURN OFF and disable or Vegas will crash EVERY time you render!! No using GPU acceleration (my main reason for the upgrade to!!) No CUDA, nothing works!
The ONLY way I can get Sony Vegas to RENDER is to restart and render while in SAFE MODE.
Also, I have had ZERO success with DVD Architect 6 in making BluRays! It CRASHES EVERY time! (It makes DVDs okay, but any time I attempt to make a BluRay it crashes saying there is a BUG in one of the DVD Arch. system files! (And yes I have tried uninstalling, re-installing, using different & simple BluRay files,.. nothing!)
I have WASTED 10 blank BluRay discs so far!!!
This Vegas 12 upgrade is a SCAM - just like Microsoft ("Let's Make Windows 8 because it's a new year & we can force them to buy a new upgrade even though we haven't fnished Win7 yet!!")
If I hadn't found the "safe mode" workaround, I would be saving for a REAL NLE from Adobe -- even though I have been A Vegas user since Vegas 6!

@ShannonShaw
You speak big words for someone that doesn't even show his system spec. VP12 is an extremely stable software provided you have the right hardware for it.

VP12 has so many more features then any of the versions below VP11, but, if you don't need them then there is no need to upgrade. Also, if you upgrade you have to keep in mind that VP12 only comes in 64bit and it prefers, like me, Windows 7 and a graphic card like Nvidia 500 series, GTX 560Ti up to GTX580. Those cards run best on driver 296.10, hence the need for Windows 7, preferable the Pro version. ATI cards seem to work well too, even later models.

Here is again my post about VP12 and GPU acceleration: http://www.sonycreativesoftware.com/forums/ShowMessage.asp?Forum=4&MessageID=859391

ShannonShaw... you are so wrong!