I passed ISSAP today! First attempt!
Last April, I bought the ISSAP self-study course from ISC2. It came bundled with an exam voucher and with CISSP refresh course videos. That was the study material I used. I also had a quick look through the ISC CBK for ISSAP and I don't recommend that book. Too hard to read and the material seems out of date.
Further more it helped A LOT that I have a big knowledge and experience of technology with operating systems, networks, cloud computing and security operations.
My advise to those who have recently passed CISSP and are considering ISSAP:
a) Get plenty of experience and skills working with Cloud computing.
b) Make a plan to take the ISSAP exam in 12-18 months after getting the CISSP.
c) I recommend the ISC self-study course.
Now I guess, the next step would to find an ISSAP certified to endorse me. I don't think ISSAP is self endorsed like CCSP, is it?