I have been to a bunch of galleries and seeing a painting in person doesn't usually make a difference for me compared to seeing it in a book.

Guernica is one of the few that did. Perhaps because it's massive compared to other well known paintings.

So, I just want to say, I second your recommendation for seeing it in person.

One of the things that made seeing this painting a valuable experience for me was the plentiful background material it was shown next to… drawings, paintings, sketches etc. it showed the depth of creative process that Picasso employed.

One thing I have not seen discussed here is the fact that this painting was commissioned by the (Spanish) Republican government. Effectively, there is a degree of propaganda to the painting. No shade on the guy… my other favorite war crime painting is the executions of the third of may by Goya, and it was also a political commission.