Microsoft has a tool to block automatic UE10 upgrades through Windows update. You can always manually update to 10 later should you decide you want it. Info here
There's also a compatibility inspector that will help flag potential issues IE10 may experience with your own webpages. More here
FWIW, I have it running on a test machine and haven't run into any issues so far. It also seems to link to and navigate all the financial sites I've tried it on. But I haven't extensively tested it on those sites, so there may be some site-specific features that have been broken without my realizing it. YMMV.