1)Is there a difference in the high you get from snorting meth vs. smoking meth?.
yes. snorting requires more material (meth) than smoking to get high, because of bioavailability issues... i.e. - 62.7% oral;
79% nasal;
90.3% smoked; 99% rectally; 100% IV ... so as you'd guess, the oral method requires the most material (meth) to produce a high and has the longest duration of effects as well. the quicker the onset/crossing of the BBB occurs, the higher the users' tolerance becomes as well.
due to idividual metabolism issues, everyone experiences differing effects from the various ROAs. --
(FTR i've only used crystal meth...)--
Me:
oral meth: hits within 15-20min and lasts about 5hrs with a gradual tapering (yes fast metabolism sucks, kids). it fucks up my stomach ("knots-in-my-gut feeling") for about 24 hours altho i'm very hungry while on it and eat quite a bit more than usual, actually. nice lingering euphoria (often outlasting all other effects), increased stamina and motivation; heightened libido (sometimes), enhanced cognitive ability, relaxation, enhanced motor skills, *improved artistic creativity (speculation!

). very good to eat your meth for long-hours of work! (keep in mind i have ADD so meth slows everything down and i can actually process things much more easily, making me more focused and productive).
insufflated meth: i don't like this method. it takes [wastes] a lot of material that could be used to
get you going and fucks your nose up.. to me there isn't much of a rush..just more of a sudden buzzed alertness not much more intense than the oral method followed by endless hours of edginess, mood swings, and fiending for more when that awful comedown hits and you're too strung out to fall asleep.

overall it's a 2hr body buzz w/a little euphoria followed by 2+ hrs of feeling like shit till you're either asleep or you're doing more. 8)
smoking meth: absolute favorite if i'm just chillin at home, at a party with friends, anything casual... the rush is a feeling of profound calmness and relaxed mood with focus and a good amount of mental energy -- note here the difference between the mental energy (alertness) of smoking meth and the physical+mental energy/stamina of eating meth. no stomach issues.
note: mood is noticeably brighter, creating a more emphathogenic experience; rather than a cerebral high with a CNS buzz associated with oral meth use...sometimes nasal
note: duration depends on too many factors to effectively cover here...how many hits are taken over a period of time, how much is smoked, metabolism, tolerance, etc etc...
let's just say i take one nice big hit off 30-40mg..i'll be alert, mildly energized, emotionally balanced (a bit happy, actually), mellow, capable, and sociable for a good 2-3hrs. it's almost a bit like a small dose of MDMA, without any nasty comedown. i can even sleep while i'm on it and feel great when coming down (it makes me tired..but in the pleasant euphoric way an opiate would). taking more than a few hits in a day becomes pointless, tho....
perpetual re-dosing with any ROA is self-destructive. Without proper rest and nutrition the mind and body will begin to show signs of weakness even while dosed (hallucinations, fatigue, etc)...
3)Which method do you prefer better?
smoking %). then i use oral when i don't have much left or i need it to work on..in much the same way i'd take my (scripted) vyvanse or adderall for the same thing
4)In which method does the high last longer?
hmm...i would say the oral ROA, altho not everyone actually experiences a
high when they eat meth due to a lot of factors. as for me, i get a nice long-lasting euphoria extending beyond the body buzz and enhanced cognitive function...much like an afterglow
5)Any other comments you'd like to add?
plugging is supposedly the shit (pun intended). i wouldn't mind trying it just for the hell of it, altho at a time when i have a lot of the stuff lying around, because i'd be too paranoid about wasting my precious diamonds on anal efforts gone awry.
...and yes, i'm high, tweakn my face off some nice uncut...one last smoke before zzz time %)
Peace