I find these guides invaluable. The way the extension, on cover, folds out means it can be used as a bookmark to keep your place in guide. They fit into handbag without adding weight or bulk. The maps are good and I would be literally lost without them. They ensure you become familiar with the city and its transport. I did need a bus route map which I picked up at airport. And the information to purchase the 3-day travel ticket was a bit hazy. They did sell on one station but it was from a machine that needed coins which, as recently arrived tourists, we did not possess in the quantity needed for three tickets! Luckily on Deak Ferencter there was a lady seated at a table selling exactly what we needed. My only other recommendation is using BBC website to get basic language phrases which also allows you to hear pronunciation. This guide does include them and lists menu items, although most places list in English as well as Hungarian.
The guide helps you view the city and ensures you don't miss major attractions, although it does highlights other places of interest as well. It may skim the surface of history in a magazine-style but it is enough to provide awareness and be able to fit it alongside your existing knowedge of European history. I also like the quality of the photos in the guide. Finally, and importantly, the font is readable, one or two other guides I looked at were also compact and, may have been, more comprehensive but their font was too small.
Enjoy your visit, we did :-)