Truth be told, I like bursting, squirming, squeezing, holding, desperately trying to keep it in, waaaaayyyy more than I like to see peeing.
But if I see peeing, I like it the most from from the full frontal perspective. This split second before it actually comes out, when you know the sphincter is relaxing and the urethra is just about to turn into a firehose... hmm...
Back perspective can be nice too, especially if she's got really slim thighs, and her legs are spread wide enough so you can see everything, even from behind. As nice as curvy girls are, a big round ass and thick legs