I should start by saying that I'm far from being considered a connoisseur, but I've had enough blowjobs that I can differentiate and even sort them into categories.
All blowjobs are good, but some are better than others!
Basic blowjob - given before sex mainly to get a guy hard. This is good, but if the resulting sex is blasΓ©, so will be the blowjob. My experience here is that after you've you're your reciprocating; your soldier may need additional attention. The sex will be ok, because your pecker will harden, but not like it was just after leaving her warm mouth.
Blowjob as a part of 69 β this can be great, but it's difficult to concentrate while munching on your partners snatch. I've had few of this variety, but one I seem to recall is that my partner had a strange odor and I couldn't wait to right myself to just do her doggie style. There was nothing wrong, but certainly not what I'd consider magnificent.
Blowjob coupled with a hand job β this can be great if it's split 60-40 or better. I've had much experience here, but if your partner is not into it this can be a dog, and again you may want to opt for the lay. Now your partner maybe a great lay, but needs some work giving blowjobs. The fact that she tried is a good place to start and teach her to be magnificent.
Blowjob and she spits β this is great, but how much did she really care if she spits your precious fluid. Now if she spits it all over her boobs this can be great, and if she rubs it all over them, WOW. My experience has been that she will not spit, but is usually unable to hold the fluid so it will trickle from her mouth. This can be sexy or a turn-off.