His 5D and 2D can be beaten by lows like 2B or 3C, they only guard point high and mid attacks. Watch out for 6D, which blocks lows and mid, if you block it though, it's usually easy to punish.
If they anticipate you trying to punish after a blocked drive, however, remember that 5D and 6D can be special canceled into his fire punch special, which scores a fatal on counter hit. 2D is jump cancelable, and j.D has 3 frame recovery upon landing.