You'd be fine with 30mg.. 20mg is a little low imo for optimal results if you're looking for good gains... Don't run the nolva if you don't need to, if you do get sore nips (you'd know if it was gyno) as it feels sore, then take the nolva.. no point in taking them straight away if you don't need to, you don't get tits over night lol. RE Proviron etc, some use but with Dbol alone i'd leave it, at 160lbs a bit of water retention will help the gains as most of the water is retained in the muscles, if you used something like prov it would slow gains
Of course, packaging means nothing if you the product isn't any good. I sampled this Test C as part of my TRT program last summer. It draws up very well and has no post injection pain. I used this product at .4 cc (100mg) 2x week for 12 1/2 weeks. My libido and energy level were right were they should be and my perceived test levels also remained high. I did not do blood work during this time, but I have been on test for TRT for 4 years and feel confident that this is good test. I also was able to lean out really well while on TRT with this test, something that would not happen with inferior test.