I used to (a month or two ago) be able to make my units with some arbitrary text, with spaces, which helped a lot since I use a lot of different units and labels in my data, and I have no need to define special cases for each and every one.
For instance,
\SI{1}{liter soln}
would produce "1 liter soln"
However I recently updated all my packages and apparently this does not work anymore. I now get all the spaces in the units removed, so "1 litersoln".
Can someone confirm that siunitx changed recently to enforce always using properly declared units in \SI{}{}? And if so, is there some easy way to work around? To be clear I DO NOT want to define unique qualifiers and units for each case because I would literally have dozens in my file, each used once.

\sisetup{mode=text}in your preamble to forcesiunitxto typeset everything in text mode instead of math mode. Beware if you have different fonts for your text and math though, it may not look quite right :-) Out of curiosity, why do you have so many different unit combinations? – darthbith Jan 28 '15 at 18:45