I'm in agreement with Richard and Glenn for this.

If not all done with KiXtart then one of my fav utils RoboCopy can also run continuous and be set to look at given intervals for updates, but think a full KiXtart solution would be better.

As for load I don't think it would be that much of a load unless you have thousands of clients behind a 128K link in which case you probably have other more pressing issues.
Take a look sometime at how many calls your system (along with all the computers in your Org) go out and make calls to Microsoft or DNS lookups etc. Sniffing a system you'll see that it makes a ton of calls even though it seems quiet but the load impact is minimal considering how many systems are doing all this talking.