Saying it's undetectable after "just" testing it is completely bullshit. Maybe you don't get instabanned but you don't know for sure that it's undetectable until a few weeks after using it. Public hacks like this are always on the eye of Valve and if you are caught with them your acc will be flagged in a sense and will be banned later on to prevent people from coming back immediately and saying "Oh it's detected guys don't use it". They try to ban as many people using it at once so that others using it don't have as big an opportunity to avoid the VAC.