[Exim] Compiling Exim With Cygwin?

I'm interested in running either Sendmail or Exim on some NT boxen we have
dedicated for E-mail use. How much effort would be involved in getting Exim
to compile on NT using Cygwin? What kind of performance might I expect?

I'm advocating to our team a Unix MTA instead of a closed-source NT-based
MTA, which is what we're wanting to replace in the first place. I really
like the idea of having the source so we can tweak it to do *exactly* what
we want. (Oh, and the price is right ;).)

I've already asked on the Cygwin mailing list, about both Sendmail and Exim,
but haven't heard anything about Exim there yet. (Some people have done it
with Sendmail already; there are some patches floating about.) I'm
interested in hearing the balanced perspective, especially since I'm not
sure which of the two I (or anybody else involved with this!) would prefer.

Jason B.