starting postgres with several Data directories

Hello, pgsql guru

I have windows version of postgres 8.4 for experiments.
At first - what I have done so far:
1. Copied content of Data directory to Data2
2. Changed the port to 5433 in Data2\postgresql.conf
3. Started postgres from commant prompt like (F:/Program
Files/PostgreSQL/8.4/bin/pg_ctl.exe start -N "postgresql-8.42" -D
"F:/Program Files/PostgreSQL/8.4/data2" -w)
4. Started service of postgres (witch uses Data directory).
5. Test the connection with PgAdmin. Connection OK. Inserting into table of
one server instance doesn't effect second one. Everything seems to work OK.

I wanted to ask if it is OK to start several instances of postgres pointing
to different data directories? I guess thats what the data directories are
after all, but because I failed to find some assurance while google'ing I'm
asking the question. It would be a crying shame to ruin production DB
because of experimental stuff. :)

Thank you in advance.

Julius Tuskenis