yes, I have done it a couple of times. It's tough to be in the mood after you have already filled her up - BUT - it's a great taste and worth pushing yourself to do it. You will be jacking off to the memory for a long time
The last serious girlfriend I had, had the sweetest, juiciest tasting pussy I've ever eaten and I could never get enough of it. I'd eat it for as long as she'd let me before we fucked and after a little post-fuck cuddling, I'd soon have my face buried in her wonderful juices again. And mixed with my own cum, they were just that much better. I can understand that this might be a turn-off for some completely straight guys but if you've never tried it, you might find it delightful. After all, it's your cum. Me, I have no problem with it at all because I'm bi and I love to suck cocks and drink cum. I'd just as gladly eat another guys come out of a nice pussy as long as he was someone I'd be willing to suck anyway.
I've done it. I had one girlfriend who really got off on it. I'd fill her up, then go down and fill up my mouth with both our love juices, then go back up and pass it to her mouth while fucking her again. Fuck for about 5 mins, then back down for 5 and so forth. Hours just fly by.