Dickey got knocked around a couple weeks ago in Atlanta but has been very solid besides that one start. Most of his runs are given up via the long ball, but Houston doesn't really hit many home runs (only 13 so far this season).
On the other hand, Norris has been consistently pretty bad all season. He pitched well his first start of the season, but things have gone downhill from there.
I admittedly haven't seen either of these teams play at all this year so far, so if anyone has anything to add, please do.