My '11 N55 6MT has never stalled while idling, cold or hot. I've noticed occasional slight RPM fluctuations during hot idle, +/- 100 rpm, but it only lasts for 5 seconds and the motor never sounds or feels like it's about to stall.
2011 E92 335i 6MT (Space Gray/Coral): M-Sport / Premium / Convenience / Navi / L7 / InvisiGuard / Dinan Exhaust & Pedals
2011 CR-Z EX 6MT, 2008 GSX-R600
RETIRED: 2008 Dinan M5 SMG, 2006 330i 6MT, 2006 Dinan 550i 6MT, 1992 Accord EX 5MT