Never been there but it'd have to be WIN stadium. I went there to the old Kogarah oval and it was unbelievable compared to Lidcombe and that bloody 6 lane bicyle track.
For atmosphere would probably have to be the tigers home ground at L(oval)
When the Steeler were around, I liked the eastern side of WIN Stadium, Wollongong. There was nothing like watching Bears play at Noirth Sydney either.