Oxy(oral)- kicks in within 40 minutes, and peaks within an hour-an hour and half after taking it. The high starts off with a small rush feeling at the begining, rather a minor butterfly feeling where you feel really motivated, energetic and mabye even hungry. After 4-5 minutes this goes away and the high turns into a very euphoric, very warm and cozy high. You are able to nodd and can still feel a little stimulated in the sense that you feel you can do anything you want, be it lying on the couch or doing other stuff like computer, etc. It gets you high for a good 2-3 hours, after which you can still feel mellow and happy (afterglow) for another 2-3 hours, though the major euphoric and nodding effects have gone away. Afterwards the effects will be pretty much completly gone.
Methadone (oral)- takes 4 hours to peak. Within the first hour you feel, a slight physical relief (esp if addicted) and feel like you would from mabye a little codeine. Within the second hour the high can be felt, very much resembling oxy esp snorted in that you feel the opiate high though you also feel very stimulated/outgoing energetic. You might get the desire to do something with your time. Within the 3rd hour the high decreases in the amount of stimulation and starts increasing gradually in sedation (like a hydrocodone buzz would be) although the motivation is still there, you rather feel like 'everything is ALRIGHT'. You might get the desire to lye down on the couch or relax somewhere and watch some tv. By the fourth hour you will be very high, and sedated, you will be nodding out and feeling euphoric though not like the euphoria you get from oxy. But rather a euphoria that's not as 'stimulating/rushy', but the kind of euphoria that's like 'oh my god, everything is alllright', you feel like you can do pretty much anything but you will probably choose to chill out and enjoy your high. You feel the major effects up to 6-8 hours after taking it, and feel residual effects for the rest of the day till you go to sleep. Rather than an after glow, it's more like 'residual effects', where you don't feel as happy as on oxy but you feel nice and comfortable, and better than normal.
To sum it up quite nicely, many people say methadone isn't euphoric, though that's not true. For many people it is. If what you are after is a very euphoric buzz where you may or may not nodd out as much, though you feel very euphoric and sociable, and mabye once in a while if you want or try you can nodd out and feel euphoric/stimulated as well, then your best bet is either one of the following: oxycontin (oral-a bit more sedating, snorted-a lot more stimulated/euphoric though still mellow), hydromorphone (snorted- a bit more of a stimulating feeling than oxycontin, takes higher doses in order to get that plus a warm nodd), fentanyl (oral- mixed in a 500mL water bottle and sipped is A WHOLE LOT more stimulating/cleaner feeling than oxy, and the euphoria beats even oxy's euphoria, though you nodd easier on oxy) and that's about all I can think of right now. All those drugs are for people who like the euphoric/outgoing sociable type of high that oxy gives.
Other people (myself included) aren't as much after the euphoric/sociable/outgoing rushy type effects that the previously mentioned drugs give. Rather they would much rather preffer something that gives you an 'everything's alllright euphoria' with the sedation and nodding which makes them feel 'secure' and 'protected' like underneath an opiate blanket kind of effect. The opiates which give this type of high are methadone (oral- very much a solid opioid high of nodding and of relaxation and the other kind of euphoria where you want to be alone, to yourself for the high and watch tv, and escape from everything into a warm nodd and feel really good about everything, and everything around you seems to be okay), hydrocodone (oral- you want to lye around on your couch, on your own to enjoy and to nodd, and get that 'everything's all right' euphoria of relief), codeine (oral- a lot like the methadone/hydrocodone high, sedating, euphoric in that you nodd out into heaven sort of feeling you get on the more sedating opiates like the ones i'm discussing now), demerol (snorted- gives a high that is pretty unique on it's own though it resembles the more sedating opiates rather than the oxy/fentanyl type of opiates which give a more euphoric/clean and not as sedating high, demerol makes you euphoric and more sedated than codeine or hydrocodone and also gave me minor visuals if i stared at a bright coloured object, very nice, and sedating). That's about all the opiates/opioids I have tried. I would much rather preffer a good sedating high, rather than a clean/sociable/outgoing kind of high. Both type of highs are good, and both give opiate users motivation though the oxy-like drugs give this effect much more so than the methadone-like drugs. Both are good, but some people like myself aren't as much into the 'rushy' kind of drugs and preffer something mellow and euphoric like the highs from weed/benzos. While others do preffer the rushy kind of drugs and will mostly preffer the highs of coke/meth/E over the highs of weed/benzos, than the oxy-like drugs are the most euphoric for them. But what people find euphoric can be relative, just like I mentioned. My idea of euphoria is to be sedated, warm, cozy feeling, nodding and have an euphoria about everything, hence the 'everything's allright' effect.