I installed the new Firestorm Viewer last night - the recommended upgrade.
I installed the Windows 64 bit version for Second Life only.
I did a clean install.
My system would be considered "high end" by many - it is an Intel I7 based custom gaming computer running an NVDIA 970 graphics card. I run my graphics setting at the level right before Ultra.
Here are two initial caveats -
1. I crashed tonight. This is the first time I have crashed in Second Life in about two years.
I was with Benja on our sim and he had no problems, and has not upgraded, so the problem was not a sim crash. I also had internet connectivity at the time - a sudden connection loss (always a problem in Florida summer thunderstorms) was not the issue.
I will be going back and doing another install if this problem continues.
2. My cloud TGA files (in Windstorm Optional Preferences) may not be rendering properly. These are for the optional cloud versions that may be selected. I need to check this, and this could be a problem with the new install and conflicting files.
I have a second computer, a new Acer Laptop running an Intel I3 chip that I usually run at high graphics settings that I have not upgraded yet. I am going to hold off for now.
The new upgrade does seem faster, but the crash is concerning. I will let you know if the problem continues.