You are correct on the BIS Syncing. Only way (at least that I know of) is to use BES. Getting PUSH email is an easy workaround, but Reconciling is specific to BES to my knowledge.
And you should only be paying $44.99/mo on Cingular for the unlimited Blackberry package. There isn't a difference to them between BES and BIS. Mine was labelled Unlimited Blackberry BIS but I used a hosted BES and paid that same with no overage/odd charges.
As for the Hosted BES- your numbers are right on. The averages between the well known companies (Link2Exchange, ExchangeMyMail, and TheMessageCenter) are around:
$9.95/mo for ~200mb of Exchange storage
$9.95/mo for BES hosting
--The difference may come in the activation costs.
I personally use Link2Exchange, and pay a total of $21.95/mo for 400mb Exchange hosting, BES, and Postini Advanced Email Filtering (its a great filter). I have had no experience with the other providers, but I can say L2E has been wonderful. It's worth the money to have everything sync'ed OTA, and have the support I need.