As of Version 33.0.1750.115, at least that's the version I'm using on my Linux Mint 16 box, the "Enable Instant Extended API" flag no longer exists. I just sent Google some feedback on this. I won't say that I was as polite as I am normally. But, they needed some reminding. They seem to forget that people use Chrome at work and something like this could have a serious impact.
The only option now is for those of us savvy enough, (and who can remember to do so), is to either go incognito, Ctrl+Shift+N, full time -- a pain -- and to manually delete browser history on exit anyway.
I left Firefox a couple of years ago because performance was just horrible and because sandboxing was apparently a totally alien concept to them. I don't know what progress Mozilla has made on those issues, but I wonder if Opera is any good? I'll have to check if it's available for Linux. But, I bet Opera has its own set of schizophrenic traits.
Update:
Wouldn't you know it, I found an extension to redirect the new tab page in their App store. I can only hope that it's been properly vetted. There are a few to choose from. For the record, I arbitrarily picked 'New Tab Redirect!' by James Schubert.