i'd go shimano, i've been running saint for a while now and love 'em. the (old school) xt's i've just put on the titus have had a few rides and feel just as good when it comes to normal riding
You may struggle to find a complete chainset in old skool XTR as these were phased out at the end of 2002. You can still buy individual parts as spares but it does get expensive.