Ethically I think it's a terrible idea to recommend a ''speed-ball'' of any kind. Good on you for the warning. Sorry you had a stroke. Glad you are okay, hope you made a full recovery.

Most people who die from a "speedball" (which is traditionally mainline coke and smack) die from respiratory depression. The opiate's effects last longer than do cocaine's, so the user ends up ODing on the smack.

the only flavor of speedball i've ever done is mdxx and opiates.  on larger doses i noticed some really strange reaction in regards to water retention.  i would drink a sports drink (ones that includes electrolytes) and it would just go right through me.  my cheeks got really swollen looking (a possible sign of severe dehydration) and i could tell shit was not going well for me.  no matter what i did i couldn't hydrate my body.  so i took a klonopin and then i was able to hydrate properly again.  that's happened to me twice, once in a mixture of mdma/oxycodone/codeine and another time on a mixture of mda/hydrocodone or perhaps oxycodone i can't remember.  but anyway i was terribly dehydrated yet anything i drink would pass right through, i even ate a little salt but it didn't help.

in the case of mdxx i think that opiates don't enhance the experience whatsoever, in fact they dull the experience.  they're great for the comedown or the day after though.  the only reason i mixed them was because of an existing opiate habit and decided at the last minute to take mdxx those nights.  i try to not mix them but i ended up mixing them in large amounts those 2 times due to not pre-planning and wanting to roll really bad, regardless of what i had taken already.  i've taken mdxx with opiates in small amounts with no problems at all, aside from the opiates dulling the experience a bit like i said.  they rob me from the mdxx-onset-poop that i always look forward to and i never roll like i should.  sure, i'll be rolling and feeling good but it'll never be as good of a roll as it would've been if i didn't take any opiates.

the closest thing to a speedball i've ever done aside from the mdxx mixture is some red bull and percocet, great combo for being out dancing with some nice euphoria.  i'm just not a fan of stimulants in general unless they're empathogens or psychedelics.  what's weird is i was far more productive (and happy) on the right amount of hydrocodone or oxycodone than when i had tried d-amphetamine or meth.  too much and i nod out, but just the right amount puts me in a great mood with energy to get tons of shit done.

Overdoing speed-ball sounds like a pleasant suicide!

I feel like I have to post a safety disclaimer on over 75% of your post.