I threatened moving my business elsewhere which coincidentally brought a follow-up email stating they had just removed the agent checks
Unless you meant "coincidentally" non-ironically, yeah, I'm suuuure that that was their impetus.
IE is so much a part of WIndows that "firing up IE" doesn't really mean that much. No more than opening the IE engine within a Firefox tab anyway.
Having web sites that you know won't work in Firefox automatically be rendered using IE is a huge time saver: activate the URL bar, type in the URL, and hit return, as opposed to Start->Programs->blah blah blah->IE, select URL bar, type in URL, remember that when IE finishes loading its start page it resets the URL bar, enter the URL again, etc.
Hopefully the inconvenience will be incentive to voice your dissatisfaction in the right direction.
Either you're inclined to complain or you're not. Saving yourself time isn't going to modify that.
When I try Chrome I'll be doing it for the ability to run one tab without affecting the responsiveness of another.
Try entering "about:%".
I only wish all its issues could be remedied with these types of band-aids.
Out of curiosity, have you ever been satisfied with any piece of software ever?