Just wondered if anyone with some urban flying experience would care to share some tips on how to best fly in a concrete jungle such as this one in downtown LA: http://vimeo.com/101231747 I've done most of my flying with a P2 FPV rig in rural settings and am just putting my new P3P through some careful tests/initial flights. I plan on getting far more experience with the P3P before attempting any urban flying, but I'm wondering how other brave souls have handled issues unique to the urban landscape. For example, the linked video at 1:24 sec with medium-tall bldgs all about, concrete as far as the eye can see. Where do you take of and land (hand catch?) from this kind of setting? With no grass areas available do you typically take off and land from ground-level concrete areas after using some type of magnetic sniffer app to look for an area safe enough to do so? (so that any hidden metal won't cause compass errors that would effect flight) I presume that a good calibration from a flat grassy field should be left alone and not attempted anywhere near concrete, but looking for any advice here. Also wondering if you can safely launch down between valleys of buildings presuming a certain threshold of satellites and LOS, or if trying to gain some elevation on top of structures is a valid strategy. And are you guys typically using standard P-GPS mode for your urban flights or going right into A-Atti, or F-course lock for certain environments/effects? Thanks in advance for any advice.