Its easy money to make, selling it you goe yuorself a mil , the behemouth skin isnt that pricy just requires some skill to find a leather 100 friend with lvl 55 gold smithing then you got yourslef a hawt piece of armor
Depends what job your playing, this is definatly very nice for soloing if your a job that dosent get heavy armor types, and although this may be a foreign concept, Most people carry interchangable gear...just macro this on in fights and the take it off to run around-- Armor does not reset TP.
I don't know if this is worth buying or not, but it seems to be. All of the peices to this set sell for over a million each on Phoenix.
Reduced movement speed is like the opposite effect that you'd get from Strider Boots. You would run slower, but it wouldn't effect your delay for your weapon.