Here's a review I wrote back in June 2011 on the (waterproof) VS150 series: http://www.fishingworld.com.au/news/tes ... taal-vs150
It's now end March 2012 and my VS150 got another walloping today on the yak. In more than 18 months ownership and smashing it with often full saltwater immersion I have NEVER needed to open this reel - not ever. It just get a freshwater rinse after every trip and about every 2 months I spray the outer case with Lanox.
Upsides: Absolutely 100% waterproof internals, really tough, strong drag, good line capacity, loud clicker, defintaly the best yak reel I've owned for reliability without needing maintenance.
Downsides: Weird hourglass line lay (on my reel with 30lb braid), drag knob a bit small and you really need to work it to tighten the drag, in lumpy or very windy seas the line sometimes lifts off the unbailed roller bearing - For the yak I'd choose the bail armed option if I had a choice. Also, the cranking doesn't have that mega smooth feeling of Stellas etc, where the handle keeps spinning. It feels more like a solid workhorse that you keep winding up.
Re: The VM series - It isn't classified as "waterproof" so if I had the $$$ I'd choose the VS series because they are.