I don't find the residual stim that bad personally - maybe oral/nasal routes would have longer resdiual stim, but when i vape i find i can usually sleep at most 4 hours after my last go (it's in and out quicker i guess) - i still wouldn't recommend anyone vape though as it's undoubtedly bad for your lungs (and tongues) - but then i wouldn't recommend anyone do anything really (too much responsiblity); but sometimes saying you think something isn't shit becomes a recommendation in itself.
With that said, i must be lucky because i don't find this stuff as troublesome as some on here - i certainly don't find it as compulsive as crack: i find it moreish and end up thinking 'why not' and doing more, but when i have crack there's no question involved, i'm doing/getting more. Also i find there's a limit to how long i want to binge: i find going for longer than 24-36 i start to not be able to be functional anymore (ie use music software - why i use the stuff) - so i usually abort by then. I have tried binging longer than this (just to see) but i just get into a spaced out state where i'm not really doing anything productive, which is nice at the time, but in retrospect not worth the wear (i find the same with all stims i've tried).
Also i always give at least until the next weekend to recover - dosing drugs every day for any stretch is a bad idea for me, especially ones with any effect on serotonin (i don't think taking 5htp is any solution to serotonin-depleting drugs - it doesn't remove the need for serotonin recovery, just reduces the intensity or maybe provides some of the serotonin as needed (although you'd get it from just eating meat and milk i'd guess))
Reading all the other posts i need to add a big old YMMV here (ie err on the side of caution if you think you have any addiction problems)