De rien Stief (Bienvenue in international French). The benefit of not having firewall is quite obvious. You can receive connections from firewalled hosts. This mean that you can be an ultrapeer for everybody. Moreover the greatest benefit is that your success rate for three stars results is much better since three stars results are often people firewalled that can't accept uploads to other firewalled hosts. As a result, the speed you get from them is often very fast (they upload less).

Ciao