I was recently in your situation, except I was using a RTP. After enduring several falls with one foot in and one foot out, resulting in banged up shins and lots of blood in the boat, my partner insisted that I change to double boots (I think he was more worried about blood in his boat than me). I much prefer the double boots and wish I would have switched sooner, not to mention there's been no more bleeding, or any other injuries, after LOTS of falls.
But as 6balls says, its personal preference.