I don't think that FM-200 has the same issues with long-term damage to equipment that Halon had. Most of the datacenters I go into on a day to day basis use FM-200; seeing one with dry-pipe sprinklers is unusual.

Once upon a time I had a customer with wet-pipe sprinklers...and a baking tray underneath one that was leaking, with a little tube taking the water out of the baking tray out of the datacenter and into a drain in the bathroom. It was an impressive bit of engineering. I was told that the one server that the leak destroyed cost them $50k to replace, without regard to the downtime cost.

There's a reason my nom-de-Internet is what it is -- if anything can go wrong, it will go wrong in my presence. I've managed to avoid being present for an inadvertent fire suppressant discharge, however.