These types of prohormones are safer on the body as they do not use methyls to get into our body therefore being less taxing on the liver. This means much less stress on the body. Seems like a win-win? The only downside to these types of prohormones is that they are usually less powerful than the methylated ones.
Because they are less taxing on the body, it's much safer to stack non-methylated prohormones. You can stack them with each other or even stack them with methylated prohormones.