Re: Runnerbeans... "shine or rain" used to be their motto, so yes they do offer their tours regardless of the weather. They're not official guides, yet their guides are very knowledgeable and, so it seems, they all are excellent conversationalists who engage with their clients. I've had a number of foreign friends visiting that have used their services and they all were very satisfied. I've met the owners running this small family company, Gorka and Ann-Marie, a Basque-Irish couple, and I have to say they're the most amazing people I've ever met in the tourism industry. They're so passionate and so professional that I wouldn't hesitate to recommend them.
The issue about being or not an "official tour guide" is an old dispute here in Barcelona. Official Guides are university graduates in Tourism that have taken an exam (sort of like a "bar" for lawyers) which recognize them as being qualified for this job and entitles them to officially offer their services as tourist guides. This "distinction" allows them, among other things, to accompany their clients into museums while acting as their guide. Non-official tour guides cannot enter the premises while acting as such. As in all industries, among the official tour guides there are good ones (and very good ones!) and bad ones, yet having this "bar" doesn't necessarily mean they're 'good enough', sometimes you'll find guides that are very knowledgeable but they're awful at presenting it in an engaging manner to their audiences or their attitude is far too 'robotic' -if you cath my drift!
On the other hand, non-official tour guides fall into two categories: the ones that are good at soaking in knowledge and good at transmitting it to others in an entertaining, and often professional, way. The best ones can be, IMHO, as good as any official tour guide and the dispute about being official or not becomes quite irrelevant from a visitor's point of view. In my opinion, Runnerbeans fall in this category. And then you also have the pirates (a.k.a. the gun-hoes) which shamefully keep offering lousy services full of stereotypes and baseless narratives that would easily embarrass any Barcelona resident who loves and knows a bit about this city. I must say that the latter is more prevalent among a certain type of expats.
In short, official or non-official in Barcelona wouldn't be, for me, a decisive dealbreaker; I would rather look at other factors (reviews, price, terms, product offered, etc.)