in my opinion IBM 150 level is similar to Sun SCWCD. I got my SCWCD and two weeks after I did the IBM 150 Test. In this period I studied the new topics, like web services, ejb and jsf that don`t contain in the Sun`s test.
But I think the IBM`s test is more general, not so deeply/specific like the Sun`s test. There are more topics in the IBM 150, consequently there are less questions per topic.
I haven`t studied specific material for the IBM Test, just the SCWCD`s Resources and the EJB/Web Service specification.
SJCP2, SJCP5, SCSNI, SCWCD1.4, SCBCD5, SCDJWS5, SCEA5-I, IBM ICSD, IBM ICAD, BEA BCDWS9