Re: sage vt2 vs st croix legend ultra(8wt)
The sink tip lines, while casting differently, should not actually be any heavier than the Rio Mainstream line you've got.
Dude, that rod is a broomstick, period. I am a 5'10" 240 lb guy only 6 years out from playing NCAA football, and I have to really horse that rod to make it work. You'll need to learn to double haul powerfully and well to really get its full potential out. The guy who sold it to you ought to be willing to help out with this.
Either that or you can overline it with a 9wt and be slinging that much more line around all day. Good luck with your chosen route.