I use both Libra and Microsoft. There's a big difference in my ability to interact with the world. I want to use LibreOffice whole hog because the interface is relatively stable from one version to the next, but I've concluded my government actively works to shut down open software and open documents, as it races towards "e-gov."
I loved the pre-ribbon MS-Office interface. (e.g. Office 2003) It had a semi-understandable philosophy of organization, toolbars were stable, easily customized and it took very few clicks to get anything done. However, each interface "improvement" seemed to thumb its nose at fans and anyone "invested" in Microsoft. It meant more clicks and time to do the same thing, in addition to nullification of my muscle-memory caused by the hunting around, it also destroyed any time investment I made in setting up reasonable defaults, like single line spacing between lines and investments in menu customization and pre-programmed footer standardization, such as "server\pathname" and "page y of x" in every footer. With the introduction of the ribbon system in 2007, I tried switching to OpenOffice/Libre Office and liked the more conservative menu system, but am concerned that it, too will try emulate MS look and feel.
With the introduction of a blindingly white, thin texted menu visualization system in Office 2013, I just want to say F.U. and go open-source whole hog, since Microsoft regularly says F.U. to people, like me, that pay them money.
The issue that prevents me from going whole-hog is that various agencies of my government send out mandatory regulatory response documents to businesses using the latest versions of Excel, using Excel's proprietary features (macros) and I must fill in the blanks and respond by a certain date. When I try to raise issue with this, the attitude verges on "How cheap of you to ask for something in a different format. Smart businessmen invest in new software and try not to be a pain to their regulators." Consequently many businesses work downstream with their vendors (often small business) the same way. If my government was truly serious about breaking up a monopolies, it would stop mandating use of specific brands by putting out e-forms that didn't require a particular brand of software. If it insisted it needs to use Excel internally, at least, export to another generally usable format that doesn't require a specific purchase.
We're actively contemplating cyber-security laws requiring that citizens have only secure computers or be subject to fines and/or disconnection. I expect us to make a proprietary mess of that, too.
I actually don't mind monopolies when earned by consumer choice. I just mind monopolistic behavior towards customers who have no reasonable choice, reinforced by government action.