I have quite extensive experiences with speed (racemic amphetamine, the stuff that's mostly sold here in Europe, Adderall is almost completely unheard of) and to a lesser degree with meth. I haven't touched either of them (well, I took one line of speed last year) for almost 10 years now though.
Like many here (not all though) in Europe, I preferred racemic amph to meth. There are several reasons for this. One of the most important is the comedown, which is absolutely horrendeous with meth and lasts much longer. Meth keeps you awake for much longer after the desired effects are gone. The other is the better mental focus and increase in motivation speed gives me. Meth is more tweaky (yup, more euphoric, no doubt about that) and feels more rolling, while speed is more straight-forward. Speed was always the standard drug to start a party evening with back in the days (MDMA and other drugs were added later in the evening). Very social, was great to kind of prepare you for the coming night with (although it was used through the night), before the really really fun started. It was never the main drug of the evening, as it wasn't euphoric enough. I guess with meth the difference is you don't need much else, it's euphoric enough on it's own.
The shorter duration of speed can be seen both as a plus and minus, I mostly snorted it and there was the need to redose every 2,5-3 hours or so (insufflated, orally maybe 4-5 hours apart). With meth there's not the need to redose that often. Then again I've felt like a suicidal trainwreck after weekends with no sleep (Friday to Monday without sleep, great feeling at work Monday morning) and almost no nutrition besides fluids with speed too, and had horrific comedowns from it too.
In retrospective I feel both are equally stimulating, but meth has a higher affinity for dopamine and is more serotonergic, hence the greater euphoria with it. However if I would have to take either of them, I'd take racemic amph because I like to feel clear-headed with stims.