If a government agency ever suggested IE be avoided, that info is very definitely not recent and if there was a particular security flaw as the basis, it was fixed. There are new exploits all the time, for all software, and it's important to keep updating with patches and hot-fixes. I recently ran a security scan on my own computer, and found it had over 200 critical issues, about 197 of them stemming from Apple iTunes, which hadn't been updated in a while. I updated iTunes and then it had only 3 critical issues, and they were related to other programs. I'll scan the same computer again later today to see what new issues have developed.

If you're using Windows, I recommend IE.

IE is part of the Windows Operating System and is designed to be aware of all applications you are using simultaneously, and will allocate resources appropriately. This means, if you have several tabs open in IE plus several items in Outlook, Word documents, Excel sheets, etc. all at the same time, Windows will try to allocate memory and processer power evenly/appropriately among these applications.

Alternate browsers (Chrome, Firefox, etc.) are designed to take as much memory and processing power as they can to give you the best possible experience in the browser. This will cause other programs to run slowly if you are involved in Browser-intense actions on your system (for example, a lot of tabs open with active content).

Another consideration is updates, security patches, etc. Corporate IT departments and Managed Service Providers can centrally deploy updates to Windows based applications globally. We cannot do this with Chrome or Firefox. Firefox is even worse than Chrome in this regard because when it is updated for one user on a computer, it is not updated for other user profiles on that system – i.e. all profiles on the front desk computer, or shared admin/spare computers. In addition, both Chrome and Firefox are ‘freeware’ applications, with many unsafe plugins available. These lead to security holes, and possible avenues for malware, viruses, and hackers. Companies can centrally control policies and settings for IE to prevent users from installing unauthorized plugins.

IE tends to be slower that these alternative Browsers due to its built-in security features – which scan for threats or unprotected sites. These security feature are continuously being updated and tightened, and are strongest in IE 10 and Windows 8. However, these securities often tend to be too extreme, and users or IT managers may need to adjust these settings to improve IE performance without compromising security.

Also, if it's the spell checker you like, they finally built that into IE 10. We have seen that some web sites don't recognize IE 10 or render properly because many right-brained web designers (who view Microsoft as "The Man", and prefer free open-source software) tend to have a bias and don't test their work for IE. There is a compatibility mode in IE that usually fixes that.

Edit: PS -- I don't recommend Chrome, because I have privacy concerns with Google Terms of Use. JMHO. YMMV.