Citrix – is it any good

My company is thinking of changing from an ordinary windows NT4 based network to a citrix based netowrk. I’m not sure yet what citrix product may be used, but I’ve been reading up on their MetaFrame setup. I’ve also read up a bit on their wireless setup. Have any of you used a citrix network, and are there any major flaws? My company has about 100 staff, including people who dial in, road warriors and 3 offices that are connected to the head office through an always on connection. Any thoughts?