What WC gives is what Quake gives tho (-4096 to 4096 on each axis), but you may exceed many other limits (32876 of mapnodes I assume and so on).
Okay, let somebody smarter than me speak :E
By The Way
What is the limit of entities in Quake?
I Don't Know The Upper Limit Of Entities
for Dark Places, but the 10000 Hell Knight level demo is pretty impressive.