Slowdown in VS.Net 2005 with Code Analysis turned on

I'm editing a file that is not unreasonably large -- 300 lines or so. It
is a test class, so about 40% of that is made up of 10 unit tests or so,
another 40% is made up of a bunch of nested, private classes that support
the tests, and the rest is the class under test.

With code analysis turned off, things are nice and snappy. As soon as I turn
analysis on, which I'd like to do to get Alt-Enter behavior, R# drives the
system load up to nearly 100% after every change.

I assume that this is beta behavior and that the analysis will be perf tuned
as you go, right. Right now the behavior is just about unusable.

Thanks,
bab