I pretty much stick to IE 11 and I found out the hard way using the MS media creation tool that MS will no longer allow users to directly acquire the 1703 iso. I later came across a tech site that confirmed that this was in fact the case and ended up at a 3rd party website of windows users who had catalogued the iso for their users so I got both the 32 and 64 bit versions and placed them on thumb drives for future use. The next time I clean install I will at least start with 1703 as the base OS rather than being forced to do multiple updates to a clean install.
As I've said elsewhere, you could get the IT Administrator's "full" version of the build, or go through Update.
On my second pass at going from an (image-restored) build 1607, I was able to get to the link through update that installs the Win Update Assistant. If anyone asks, that's what I tell them:
1st, wait for Windows Update to notify you that the new build is ready. MS is apparently providing that notice in groups of users and machines, and if you haven't got it yet, you're best to wait.
2nd -- first thing to do if you go to the linked page with a build-1703 download button, is SAVE the FREAKIN' LINK! If you back out of it, I only can say from personal experience that your Windows Update will be perpetually at "0% Downloaded" per the KB . . . . 240 WU assistant.
3rd -- Once you get to that link, create your USB "clean-install" of the new build first. Maybe even make the ISO for burning a DVD of it.
4th -- disconnect any unnecessary data drives. You would have had to do this before getting to the download link (unless you saved it) and initiating the upgrade. Delete any SSD-caching volumes. Delete all Ram-caching of disks.
Even for doing most of these things (I left my data drives attached), my dual-boot BCD was partially borked. I could get into either OS, but the menu didn't function properly: it would boot directly to Win 7 without the dual-boot menu when you would EXPECT to see the dual-boot menu. I could get to Win 10 by a restart from Win 7, and the dual-boot menu would appear.
Macrium Reflect repaired it, but I had to use it in two iterations: first to "fix" Win 7; second, to add Win 10 after giving the Win 10 system volume a drive letter under Win 7.
Go figure. I know people are having troubles with it. I'm only happier than a pig in s*** that it's clear sailing now for me . . . .
As for IE 11 and Edge. At first, Edge was a nuisance. Then I began to appreciate it more. I find myself using IE 11 less and less. And somehow, for either, Build 1703 has "fixed" an occasional situation where I'd have 5 or 10 tabs and sites open, and the browser would become unresponsive (under build 1607).