Essbase or MS Analysis Services - LONG

We need use of multi-dimensional analysis tools, and are being pushed
towards Hyperion Essbase by our home-office IT staff.  I have started
looking into the tools and have some reservations as to whether
Essbase is the right tool for us.  Please advise if you can.

We are a mid-sized, wholly owned subsidiary of a very large company
(our owner is on par with GE).

We need a tool to use at our site, not to be used by the home office. 
We don't deal with multiple currencies.  We don't deal with
consolidations.  We do populate a financial template, which is
uploaded the home-office consolidation/ financial reporting tool.

We primarily need a system for financial analysis and reporting. 
There is also a need to operational analysis.  Financially with have
the standard dimensions (year/qtr/month, scenario, account, cost
center, etc.) and also about a half dozen other dimensions. (maybe 10
in total).

Our financial and operational data resides in MS SQL 2000 relational
databases (we are tracking roughly 500,000 transactions a year).  Our
business is constantly changing, and operational metrics regularly
change as well.  We have roughly 5-10 users who need direct access to
our OLAP database.  Our data tends to be very sparse.

There is another division in our company that used TM1 a long time
ago, and has migrated to Essbase 6.1.  The current plan is that we can
utilize the Essbase implementation at this other site.  We will
develop our own cube structure, and push our data to the other site
over our WAN.  The only Essbase components available are the basic
Application Manager and Excel Add-in tool.  Our business model is
completely different than other division, fwiw.

I have a little experience playing with MS Analysis Services, and as I
study the 1500+ page Essbase administrator's guide (Vol 1), I am
noticing Essbase seems a lot harder to deal with than MSAS.  Example:
Integrating our source data to Essbase, maintaining the data import
Xrefs, building the initial structure, and user security all seem more
cumbersome.  Maybe if we had budget to buy several other Hyperion
tools this wouldn't be the case.

I've also noticed that the Essbase excel add-in doesn't seem as
flexible as some of our users were hoping.  Many of our users have
previous experience with Hyperion Enterprise's "Retrieve" excel add-in
and were quite happy with it.  I don't see the same ability in the
Essbase add-in (referencing back-end  OLAP data via a formula within
an individual cell).

The initial costs of Essbase won't be that high for us, but we are
still budgeting ten's of thousands for consulting fees to help get our
cube structures setup.  Since we already own MS Analysis Services, and
our Financial SQL Server box is more than robust enough to handle
additional workload, it seems to me we might be heading the wrong
direction.

If I start pushing that we should consider MS Analysis services,
coupled with one of the popular excel add-ins it will, at a minimum,
delay our Essbase implementation.  I am an experienced accountant and
database developer; I feel I could develop the OLAP structure on my
own using MS Analysis services and save the company money, maybe
providing a better solution.

I don't want to "make waves" unless I feel strongly that I am right. 
What do you guys think?  Btw, I tried to get the company to subscribe
to the OLAP report but that idea didn't fly.

Thanks for any advice you can offer.