If you are set on attending VT in the future you should strongly consider going to CC for two years to take your engineering core courses. The CC system has an articulation agreement with VT so that all of the credits will transfer.
College of Engineering
Students will be guaranteed admission into the College of Engineering after completion of a transferable engineering associate’s degree with a minimum cumulative GPA of 3.0. Students are encouraged to follow the checklist below as they progress through the associate’s program. For details please refer to:
Articulation Agreement between VCCS and the VT College of Engineering
Virginia Tech Transfer Guide Articulation Agreements | Applying as a Transfer Student
I don't know how many courses would transfer from JMU or GMU. JMU isn't going to be up for ABET accreditation until this year so you might want to avoid them.