installing a radiator

Correction: MP and I agree on improper operation of cast iron baseboard radiators with single pipe steam *as the length of the radiator increases.
I like 2 to 4 feet. And will go for 5 to 6 feet in a pinch. No more than that though. As the above referenced heatinghelp.com poster informed, he can hear some water sloshing internally at 10 feet