Actually, I thought this was pretty good. Your voices actually sounded like different people.
I noticed that your words and sentences have a constant rhythm to them (I don't know what it's called). You could make it more varied. Holding out consonants, vowels and things of that nature. "Well Aallright then."
Personally, following this advice would make it better for me. I'm no voice actor, but I hope I helped.
Thank you for the feedback, CorrosiveEyes; your advice is most certainly helpful!
I think the reason why I think everything seems to be done so quickly is because in order to make an effective demo reel you have to be able to fit in as many different voices as you possibly can, but my approach here is kind of dialogue heavy (with the same voices having more lines than usual) so the opportunity to switch it up wasn't really available to me without bogging down the overall pace of it.
However, I can most certainly see where you're coming from and I'll definitely keep that in mind when I start working on my demo for 2013!