First of all, I might contact K2 and tell them they should make it a requirement that anyone that buys the new Seth's be able to spell V-I-C-I-O-U-S properly. 
That aside, Iggy is correct. I originally mounted my 189s at +5 thinking it would make them a bit more agile as my everyday ski. However, upon getting into deeper snow for the first time on them, the tip dive was enough to make me want a change. I can probably tack a bit of the dive up to early season bad form, but I'm extremely happy with the remount at +3. I've found some deep recently and am conviced that +3 is the $$ spot (for me at least).
You need to take several things into consideration when choosing a mount on the Vicious. First don't worry about the mount graph being off, it just confuses people. Also, if you are using it as mainly a freeride and deep day ski, I'd say keep it further back than further forward. Also, take into consideration your height/weight. I'm 6'3" 190#, so the way I pressure the ski at +5 will be quite different than someone the size of Seth.
I've got more suits than Liberace, but less than Eastvailhucker.
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