acne is just anoying, gyno is kinda serious cause it could be permanent, water retention makes you look a lot bigger, you end up loosing most of it when the cycles over.
Anavar is great, i've heard you have to really hit it to make it work really well, side effects aren't permanent unless you don take any post cycle therapy (pct) (post cycle therapy) mostly made up of anti-estrogens like Nolvadex, Arimidex, Clomid, ect. just research, you'll find your niche big guy.
good luck