Personally, I rate kratom waaaaaaaaaaaaaaaaaaaaaaaaaaay higher than codeine, DHC and even morphine for that matter. Really did take me by surprise just how incredibly good the stuff is. I'm not familiar enough with it to have much of a grasp on strains but of the few I've sampled I've had ones that are significantly more euphoric and sedating than morphine (and also lacking the excessive itch even without additional antihistamine) and ones that are significantly more perky, euphoric and pleasingly stimulating than codeine (by a country mile) and quite frankly give some of the more hallowed opies a run for their money.
Amazingly good stuff in my opinion. Although it's worth mentioning I've only used it relatively few times so never developed any realy tolerance and I also don't find the taste to be in the least offensive. The anti-moisture effect of taking the powder "neat" as it is is somewhat akin to taking the cinnamon challenge admittedly (but definitely doable) but seems to be more effective mixed into a yoghurt and consumed on an empty stomach.
I rate the stuff highly and was about as doubtful as it's possible to be about the stuff for almost as long as I've known of its existence. Quite honestly I wish I'd given it a go sooner cos I found it to be sooooooooooooooooo superior to pretty much all of the common opies (heroin aside) it's untrue. I'm currently on a bupe script so can't indulge but if it weren't for that I must admit kratom would be my opioid of choice with my only concern being how rapidly tolerance appears to develop from what I've heard and how unpleasant, extended and tramadolesque the w/d from siginificant habitual usage apparently is.