I have to say that some people seem to do fine on Stan, but I think they are the exception. Most will experience some rather unpleasant sides from Stan--some, of course, more than others. However, even if you don't FEEL any side effects, Stan, in my opinion, is just to harsh on lipid profiles for me to feel safe using it: 6 mg. ED lowers HDL by an average of 33%! 6 mg.!
After my last short (5 week) cycle--which was the third in a row utilizing Stan--I got a mild hamstring tear even though I was in a cutting cycle and, thus, not trying to train super heavy.
My joints also hurt like hell, and I just felt...well, crappy.
Anavar, on the other hand, makes me feel like a Spring chicken! Seriously, Anavar is a very "clean" anabolic. Very seldom do people experience any sides to speak of. Anavar has--psychologically speaking--the exact opposite effect from Stan: I don't feel like my joints are going to crumble, I'm not stiff, flexibility is not effected, and I sleep better knowing that Anavar is neither particularly toxic to the liver, nor likely to throw my lipid profile severly out of whack.
As for what Anavar does, rather than what it doesn't, I'd mention nice respectable strength gains, a real hardening of the musculature, increased vascularity, and modest LBM gains (especially when stacked with more androgenic AAS).
Anavar stacks well with other more androgenic AAS, as it is very anabolic, with minimal androgenic properties. However, don't suppose this makes Anavar a "weak" steroid. Anavar actually has strong binding to the AR. It is non-aromatizing, thus no AI or anti-estrogen is needed if Anavar is used solo or with other non-aromitizing AAS. One of my favorite cycles is Anavar and Tren. It works exceptionally well for both cutting and lean bulking cycles.
For those dieting, some studies have shown that Anavar specifically increases the rate of abdominal fat loss (see Cy Willson's "Steroid Dieting" article.). Not too bad!
For my money, it's Anavar every time over Stan.
P.S. Anavar is no longer outrageously expensive, which is just another reason to choose it over Stan.