I'm not a spiritual guru Nick, and I'm not an expert on prayer and religion, but something tells me that God doesn't care when or where you pray, only that you're making the effort.
There's a gentleman from my homegroup, a chaplain, he weighs about 350lbs and looks like Santa Claus. He prays in the shower every morning. Now there's a visual for ya!
If you really want opinions, post this in the Christian forum, I don't think they'll have any objection to praying while you pee either