Performance Lag on Tab clicks (Banzai or Winter '16 related)

So I think this is since the Banzai upgrade in our sandbox, but it may be Winter '16 related since those happened so close to when we discovered this issue.

We have our models on a Tab page set to run on page load.  Now that we have Banzai (or Winter '16) there is a significant lag from when you click to another Skuid tab on the same page.  The data should have loaded on initial page load, but the page does not respond at all for around 5 seconds, and then the tab renders.

In the dev console, we are seeing a ton of the same two errors repeating:

Refused to set unsafe header "User-Agent"

Failed to load resource: the server responded with a status of 500 (Server Error)

When I click on the User-Agent error, it opens up to say this:

https://afl–stage– Failed to load resource: the server responded with a status of 500 (Server Error)send @ connection.js:594

We are not seeing this in our Production org, but it has us nervous to upgrade it to Banzai until we understand what is happening here.  Any ideas?  

So, I changed my external resource from /soap/ajax/30.0/apex.js to /soap/ajax/34.0/apex.js and the errors went away, and the page loaded normally.  Anyone know if Winter '16 is actually on 35.0?  Is this something we need to watch and maintain with new SF releases - to find these external resources and correct them in our Skuid pages?

Just wanted to bump this one up in case it is a bug that needs to be looked at.  I recall that that it should “auto update” or something, but this really was an issue for us.