AutoIT suitable for SaaS app blackbox testing?

Hi All,
I'm brand new here and must confess to not dong a comprehensive search of this forum prior to posting, but I have a simple question:

I'm responsible for the QA / release testing of a SaaS application (www.sagepointsoftware.com).  I have a blackbox test battery that I manually run now, but it's arduous and takes quite a while now that the application footprint has grown.

I stumbled across AutoIT while looking for off-the-shelf test harness software.  Is using AutoIT for this purpose a good application?

Please let me know if you need more detail to give a good answer, and thanks in advance.
Rich