Domain vs table

Hi,
We have table 'user' and one column define status of user, currently
there are 2 valuse 'A' acitve and 'D' deleted.
Currently we define column as domain type ( status_domain with two
possible values)
but I'm not sure is it good solution, maybe it is better create
separate table e.g account_stats and use foreign key in account table?
In our databases we prefer 'domain' solution for column with low
cardinality and when we do not need extra fields related to values
(e.g description). I think such solution should give us better
performance when rows are updated/inserted but I've never make real
comparision to separate table. Havy you made such comparision?

Regards
Michal Szymanski
http://blog.szymanskich.net
http://techblog.szymanskich.net