I've been given the green light to order new hardware to host the FM Server 14 which is currently running on a mid 2009 iMac 2.93Ghz, 8Gb RAM.
It serves an office of around 14 people plus about 10 remote users. I prefer the Mac route and my gut says go for a nice top end iMac, 1Tbgb SSD hard drive, fastest processor and max out the RAM.
However, reading through "General hardware considerations for FileMaker Server" I'm now concerned that I should be looking at the desktop Mac Pro? Or a PC ?