If you can manage your time well, then might as well do it. It will be hard IMO (if ur going for honors etc) but if youre really interested on studying and these major would be beneficial to your future career, then why not go for it. :)
The other day, a Cisco rep (different from the guy who extended the offer to me) called me and said sorry we couldn't work out a start date for you, we understand you would like to travel, perhaps we can accomodate your later graduation date. So apparently I'm still being considered by them. But now I'm thinking of taking even longer to graduate. I'm going to end up taking 4.25 years to graduate... why not just take the extra year to complete a second degree? I really feel I haven't learned enough to create a real product; CSE is all about implementation. For example, I think I have enough general knowledge o how to select 1 of several computer architectures based on virtual memory, caching, bus, IO design, etc... but that's not what makes the big bucks. All the truly valuable products are applications of numerical inference, statistical prediction, and regression analysis. People want machines that make a decisions on their behalf.