I have been to 3 US embassies since 2004 - Moscow, Bulgaria, and Cyprus (this one I have visited numerous times). Out of all my visits, I have only once actually dealt with an American - this was when they screwed up my passport renewal and I had to elevate the matter to a supervisor. The people I dealt with in Moscow and Bulgaria were very rude. The Cypriots were nice.
The security at the embassies is intense. It is a royal pain in the backside. No mobile phones, no handbags, no car keys, basically nothing that is absolutely not needed for your visit. A paper map of Nicosia was even taken from me prior to my entry - ridiculous! How dangerous is a paper map?