Pro and Con of setting up cluster Terminal servers

We have 3 Windows 2003 std terminal servers and splitting up roughly 120
users. It's quite a pain to make sure we are no overloading on one vs
another as well as relocating users whenever a TS goes down. Wondering if
it's a good idea to upgrade them to Enterprise edt and change to a cluster
setup. Any pros and cons in such setup? And if someone can point me to
some helpful articles would be greatly appreciated.

Thanks in advance.


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