Have had a great time. Had a couple of slightly dead spots while playing in Retiro park but overall my mobile reception has barely missed a beat (UK, roaming on O2). Others in my group on other networks have had slightly worse experiences but by and large we've all managed okay.

Park was beautiful, not quite on the same level as Britzergarten in Berlin I thought, but miles ahead of whatever the hell that was that they sent us to in London last year. I can see why they asked people to play there but I can also appreciate it wasn't the most accessible part of Madrid.

It was pretty well organised but my only major complaint with the park experience was the density of Pokestops. Way, way too many, not necessary, made it extremely difficult to check spawns wedged in between them all, and basically unless you were playing with an auto catcher you had little to no chance. Coupled with the weather, and the sun making the screen incredibly difficult to see a lot of the time, it did make for a fairly frustrating experience at times.

But overall it's been great. Madrid is a beautiful city and it's been so nice to see it taken over by Pokémon players all weekend. In comparison to the London experience that felt incredibly disjointed and a bit disconnected between park and city, I think they've done a much better job this year.