One girlfriend, just before she squirted for the first time actually stopped me playing with her because she had a strong desire to pee (which is a normal feeling for squirters). She went to the toilet but nothing came out because she had just urinated 15 minutes previously. I convinced her that she should let go when she has the same feeling and she finally squirted during an orgasm. She then continued to squirt several times and I made sure that I got a mouthful which had no urine smell or taste.
I had a girlfriend who regularly had to 'stop to pee' and then couldn't when she tried. Making sure she was empty was something she always did before sex too. We had our suspicions that she might be about to squirt (and cum?) but she was never relaxed enough to just go with it, even if we were fucking on towels (she used to get very very wet). We even fucked outdoors a few times in the hope this would let her let go (mmm, lovely summer nights on the Golf course near my house...) but, despite the extra excitement my pain in my knees meant I couldn't get her to the point where she even 'needed to pee'.
A year or so later I was fucking a woman who squirted all the time and she said it had started as 'needing to pee' and letting go.
Is it urine?, I don't think so, is that because I don't want it to be urine?, possibly, I would swear blind it didn't look or smell like urine but I can't be sure because, on the sheets the next day, it didn't smell too good, just not like urine.
The girl who didn't squirt (and didn't even cum from penetration) used to, when she was very turned on, leave big wet patches of her juices on the bed. Almost but not quite in the league of the multi-orgasmic squirting woman.
One thing they did have in common was that they both produced very watery lubrication compared to other women i've known. Maybe this is to do with quantity (if she produces a lot, there is less of whatever it is that thickens it up to go around) or maybe only women who produce watery juices can squirt at all? (a water pistol filled with custard just doesn't work).
Squirting is a huge turn on but I think I prefer the feel of a pussy that produces rather thicker secretions.
I'd love to know if any squirters here produce the creamy stuff AND squirt as it would completely disprove my theory