Well, after a couple of days of dealing with a Havok™ 4 Early Adopter sim, I’m fairly confidently able to say that the Havok™ 4 program is absolutely not ready for "prime time".
It’s bad enough that the physics are sufficiently different as to cause problems for C:SI combat, but even non-physical things are borked. For instance, not once in the last two days has an object I attempted to create been created where I indicated, most often being misplaced by several meters. That might sound like a minor issue, but when you *commonly* spend multiple dozens of hours making sure that prims are as perfectly aligned as SL™ will allow, you know that being off by several meters is much too frustrating to deal with after a bit. To top that off, not once has an object I’ve attempted to rez by hand from inventory succeeded the first time.
There have also been hundreds of what appear to be Asset Server-related issues, but when I go to another sim (even a super-laggy one containing a mall) those issues simply don’t occur. For instance, I cannot conveniently edit scripts in my skybox because at least 50% of the time they simply fail to load - and even after I do get them to load, half the time they fail to save as well - which would normally indicated heavy Asset Server loads yet when I go to ANY OTHER sim it works as expected.
I’m still excited that Linden Lab® is working on a new physics engine, and they’ve done some very impressive work so far, but as a content creator who spends 90% of his SL™ time building and scripting, both of which are moderately to severely borked in my Havok™ 4 home sim, it’s far too painful an environment to work in. It looks like I will be temporarily moving my workspace for the forseeable future 
Well that sucks. xD I was really hoping it would roll out soon, but now I’m hoping LL is wise enough to wait until it’s ready.
I hope so as well. It’s encouraging that they’ve gotten as far as they have recently after years of seeming inactivity, so I hope the excitement of being so close doesn’t cause them to roll it out prematurely. Of course, the more pessimistic side of me reminds me that LL is not exactly most well known for their prudence and quality control practices.
I’ve also noticed issues with the asset servers (and a related error message) when trying to edit appearance. To be fair the error message did say to try the operation again in a moment and it was successful on the 3rd try.
Is it possible that the havok4 sims are using a different set of asset servers?
That’s a good question, Ric. I seem to almost remember reading something in the recent past about some simulators using a different Asset Server, and if that is true then it seems just as likely as not that Havok 4 servers would be clumped together configuration-wise in what Asset Servers they use.
But I just don’t know
Okay, seriously… Three times now, I’ve been standing in my skybox just doing something innocuous like testing animations, and I’ve fallen through the floor.
Not like the floor suddenly turned phantom, as some people have described it, more like my floor turned to quicksand which I slowly sunk into until finally I was freefalling. I had enough time during each such event to go “wtf?!?! Why am I sinking into the floor?” before passing all the way through.
I also had to reset my Home Location, because my previous home location, which I’ve used for months now, puts me right *inside* the floor after the sim was switched to Havok4, and would leave my avatar going nuts while the simulator tried to figure out how to separate the two.
Havok 4 is very cool, and I imagine that it will help the grid out tremendously in the long run, and I’m very glad that I get to take part in testing it, but I’m worried that Linden Lab will - in typical LL fashion - simply call it “good enough” and roll it out grid-wide before fixing all of these issues.