Deep stall demonstrations in large jet aircraft produce a good deal of an onset buffet to let you know you better get your head out of your butt and do someting about it.
If you ignore the stick shaker, and the onset buffet, it just gets more pronounced and the jet just starts to lose altitude while the nose is still above the horizion. When you unload the jet by releasing the back pressure on the control column, and allow the nose to come through the horizion it recovers very nicely. I've stalled the 727, 737, and 757. I have to tell you these aircraft recover alot better than the Bellenca Viking or the old Cessna 310.
Caution... deep stalls in jets cause white caps in the coffee.