I've used it on Windows XP and Ubuntu Linux in it's various versions since about 2009. Since January 2014, I've used it intensively for a work project where I needed a spreadsheet to handle 10 000 rows of data and afford me advanced auto-filter capabilities.
It has been an intensely frustrating experience. I have had random crashes, I've encountered unintuitive dialogs and menu options (for me, anyway), odd quirks and unexpected behaviour, bugs that get fixed only to re-occur in a subsequent version, documentation that doesn't provide examples, looping behaviour (most recently LibreOffice Calc 4.2.5 seems to get stuck in an auto-save loop, crashing and then failing to recover your file) and slowness - sorting or filtering big spreadsheets is painful, and using lots of vlookups in a big spreadsheet can freeze the application, crash it or just leaving you waiting for what feels like ages.
It has been very disappointing. I am usually the one in my workplace to advocate open source software, but from my experiences I cannot say that LibreOffice has been very reliable or robust. And, when you you realise that you are spending more time recovering from crashes, looking for solutions to problems, or trying to understand some feature of the software, then you need to face the facts.
I'm aware that there are many users who rave about the software, and I was one of them. And I realise that one can have different experiences of the software on different hardware and operating systems. I run on both Windows XP and Ubuntu 14.04, and most of the issues I've encountered I seem to have encountered on both operating systems. I've had my laptop tested and my RAM checked, and I am not experiencing significant or similar issues with any other software, or dare I say it, with Microsoft Office.
I must state that, from my limited interactions with them, the LibreOffice community and developers are awesome and their enthusiasm and dedication is evident when filing bug reports or asking questions, but this takes time and certain skills which we do not all have - after attempting to file a few, I realise I am one of those people who do not have the time or skills required. I am not always able to duplicate a problem, or use the right terminology to describe an issue or ask a question. Internet access is slow in my part of South Africa, and my internet connection speed is usually way below the advertised 2 Mbps of my ADSL line. I am also not blessed with always-on internet access everywhere. Further, my day job is in a local government environment which poses challenges of its own.
So, my opinion after 6 months of using this software in my job, is:
- It IS awesome software with great features;
- It DOES have a great team of developers and supporters;
- BUT it is not (yet) robust and reliable, and might cause you more delays and problems than you can afford in your work. Keep using it, but only for non-critical, non-production related work.
Of course, I may well be criticised for adopting this view, because the whole idea of community-developed open source software is participation - working together to make it better. I get that that, and support it. But what do you do if you just need really reliable, robust tools to do your job and don't have time or skills/knowledge to meaningfully participate? So, you really need to know what you can do and what you can take on. Plan wisely according to your abilities and resources. Open source might not be the way for you to go if you don't have the time, skills, knowledge and resources to commit to the participative, community-oriented aspects of working with it, or the time and patience looking for solutions or workarounds to problems you encounter.