Depends on what you mean by "is it worth it". The class, as written, is definitely NOT a good choice for a straight sorceror. I actually altered the class in my game (dropped enlargement at 5th level, dropped the bonus spells, added +1 spell progression level at every odd level) for the sorceror in my campaign. If, on the other hand, you do something like half-orc barbarian 4/sorceror 1, it can be rather scary -- although limited.