If you don't mind the frame weighing a couple of extra pounds, there's nothing wrong with hi-ten. Because hi-ten doesn't have the ultimate tensile strength and yield strength of chromoly and more sophisticated steel alloys, the tubing has to have thicker walls to prevent bending and breaking in use - which means more material - and will therefore be heavier.

All steels from 1010 plain carbon steel to the latest high strength alloys have the virtually the same density (~0.28 pounds per cubic inch), and the same "stiffness", or Young's Modulus (~200 GPa).