Its not that cut a dry.
It is believed hdrol converts to OT based on its structure but most of its anabolic and androgenic activity is from the intrinsic value of the hdrol itself (it is already a active steroid before any conversion to OT occurs) So while yes it has similar effects as OT (since some of it is being converted to OT and the structure similarities) it also has its own effects which is why someone can try and compare the two (hdrol and OT) since they are not the same and will give different results.
That said, I would say OT would be the better choice over hdrol (legality aside)
Of course I could be wrong and in that case I am sure jbry will chime in