I know these types of drupal vs. wordpress maintenance questions have been asked before but I want to hear from a different audience than most other posts and have a true interest in peoples responses.
Two important points before you consider responding:
1) Please if you respond provide a link (or links) to a larger complex drupal site that you have maintained through at least 1 full point upgrade of drupal (i.e. 4->5, 5->6, etc.). Your opinions otherwise are not based on real life experience and the web is full of answers from those viewpoints.
2) This is not a wordpress vs. drupal debate or any such thing. Personally, I find Drupal very useful but painful to keep current - I am curious of other folks who run (again large and complex sites - include links) in other systems and their experiences overall with the rate of plugin updates, core updates breaking the site, core updates breaking plugins, etc.
And before someone says it large and complex is indeed relative - I'm speaking of sites that are not just blogs, not just brochures, but that have active forums, customized user experiences/profiles, fair amount of content, perhaps multiple authors, social media aspects, etc.
Please only people who have real-life experiences (verifiable) respond.
My interest in this is driven as a person who has a fair amount of technical expertise, enough to write basic custom modules, hack other ones, but would prefer greatly to not spend lots of time hunting for answers and programming myself into corners that are hard to get out of.
I'm in a niche no doubt where drupal has probably allowed me to create a site with functions and of a size that would not otherwise be possible (i.e. from scratch) with my skill set. And also someone who is running a site on the larger more complex side that would prefer to be focusing more on content than on upgrade paths and long-term viability of certain modules/approaches.
Thank you for any real world input on this matter!