I will get back to you on the dimensions of the bag, I've got to dig it out.
You can't fly with both by yourself, as they have to start out the flight under the seat in front of you, they are considered carry-on luggage (expensive carry on luggage

) This is FAA regulations, not airline regulations...they are supposed to stay under the seat the entire time, but both airlines I've flown on Alaska/Continental have been very good about letting me hold a carrier in my lap after take off and it must go back for landing.
I will get back with you on those dimensions