The first couple of games that I used the Exocrine I wasnt too convinced by its usefulness, after a few more games with him though Im currently finding him to be pretty much a certain pick ever time. He's not exactly amazing but with 24" range and 6 shots that are AP2 (I dont tend to use the blast very often) I think he is another unit that brings something that is quite lacking with the rest of the 'nids. Also, the fact that he is a Monstrous Creatue means that he is far from useless should he end up in combat.