in case anyone is interested here is some info from Bill R. in regards to class I and II. the article he mentions is available on meso:
The article “Pharmaceutical differences between anabolic/androgenic steroids,” or similar title, does explain the Class I / Class II distinction and present a good deal of evidence for it but that terminology is never used. Actually Tim Patterson is the one who decided to come up with this convenient means of referring to the matter: I was just using the terms “androgen receptor mediated” and “non-androgen receptor mediated.” I like the Class I / Class II way of talking about it and now use it myself also.
Class I steroids are those which are effective at the androgen receptor. This includes testosterone, nandrolone (Deca), methenolone (Primo), trenbolone, boldenone (Equipoise),
and oxandrolone. Most of these seem ineffective in non-androgen-receptor mechanisms for anabolism, and so by themselves don’t give maximum results even with high doses though they can give good results. Testosterone however is also effective by non-androgen receptor mediated mechanisms and maximum
results can be achieved with testosterone, provided dose is quite high.
Class II steroids are those that are effective despite not binding well to the androgen receptor. These include methandrostenolone (Dianabol), oxymetholone (Anadrol), stanozolol (Winstrol), 4-AD, and nor-4-AD.
So that’s the distinction: Class I binds
well to the androgen receptor, Class II does not.
The Class II’s seem interchangeable with each other, except in terms of side effects, and except that Winstrol seems to have properties the others don’t. Other than that, there is no advantage to stacking different Class II’s in my opinion.
Ditto for the Class I’s: except for testosterone having activities the other Class I’s do not, there’s no point in combining different Class I’s with each other. Basically they differ in side effects, not anabolic effects, in my opinion.
There is a lot of benefit to stacking a Class I with a Class II, though. (In some sense, testosterone is like that: a “self-stack,” so to speak.)
Class 1: Primo, Deca, trenbolone, probably
boldenone. There are all equivalent in effect, I believe, if doses are appropriately matched, but differ in side effects. None of these seem very effective
by non-AR mediated mechanisms, but are all
effective at the androgen receptor. Testosterone is also Class I, being effective
at the androgen receptor, but unlike the first
four is also effective (or perhaps, its metabolites are) in non-AR-receptor anabolism.
Class II: Dianabol, Anadrol, 4-AD, nor-4-AD,
which all seem to work the same in terms of anabolism; and Winstrol which seems a little different.