a separate flow check valve or a circulator integrated with a flow check valve?

[housecarer]

which way is better for adding a new zone in a hot water heating system, a separate flow check valve + a regular circulator or a circulator with a built in flow check valve?

[beenthere]

6 one way, 1/2 a dozen the other.

[skippedover]

Both do an equal job, as beenthere has stated. It really comes down to how the system is piped. I've seen systems where the supply piping was absolutely nuts and totally cramped but to add a zone I need to add a flow control valve. The IFC pump is the answer to that, particularly when space is at a premium.