I don't really cum from oral because my wife has "conditioned" me not to. We've been married for 44 years and I think I've cum in her mouth twice. She didn't like it either time and now has told me that I'll never get another blowjob if I cum in her mouth. So, I'm always careful to warn her as I reach the PONR.
I love receiving oral. To me, it is very intimate that she'll take me in her mouth, kiss, lick, suck, and tease my cock with her tongue. I enjoy laying back and just having her service me. When I'm really ramped up, I'll ask her to lie on her side so I can kneel beside her head, slide my cock into her mouth and fuck her mouth.
I'd love to lie my wife on her back with her head hanging over the side of the bed and deep throat her. Never going to happen. Damn.