Either class will work great, but the general consensus seems to be that monk/shaman is a superior combo. The monk can tank pretty well (especially with shaman slow), and does a heck of a lot more DPS than the SK.
The main utility that SK brings over monk is the ability to snare mobs, plus much greater aggro control (reducing, but not eliminating the shaman's need to manage his own aggro). Whereas the monk will kill things significantly faster and improve your leveling speed overall.
See also:
https://www.project1999.com/forums/a.../t-219427.html
https://www.project1999.com/forums/s...ad.php?t=72904