yes Matt but that bike is a burly beast designed for 4X (hence the name)..... its not all about matching front and rear travel, its about getting the right fork for the type of riding.
An ETSX is all-mountain but not in the burly kinda sense.. Pikes will be fine (maybe the new Pike Air forks would be best) but have a look at the Rebas as they would probably be a great match with their 80/90-115mm travel...
I do think the Pikes seem to be aimed at a slightly more hardcore market than the ETSX though.... still you could muck about with more confidence and the A-C height means it wont put the geometry out especially on like a 120mm setting.
Oh is it an earlier ETSX meant for 100mm or a later one meant for 125mm??
keep that in mind when setting up fork height, you wouldn't wanna destroy your warrenty hopes incase something went snap.
Naw mine is a 2003 etsx-30. i really want to get a longer travel fork for it but now that you have brought the waranty to my attention maybe it isnt sucha great idea. but if i do get a new fork its gotta be somthing with SPV to match the swinger 3-way air i just installed.