for regular go-moku (which this is essentially the same) i have never played on a board bigger than 13x13. They use that at IYT...i have played approximately 200 games of that and 2 of them have filled up, both agaginst the same person (lol). 15x15 would certainly be big enough though imo!
(do skréše) Jak chceš bét decke zavčaso opozorněné na nénovjéši zpráve ve tvéch oblébenéch klobech na mloveni, možeš je stáhnót RSS kamošem s pomocó RSS ikone v pravym hornim roho léstko klobo na mloveni. (pauloaguia) (okázat šecke vechetávke)