you can stack caffeine with albuterol, but don't stack ephedrine or clen with it.
albuterol and clen specifically stimulate the beta receptors, whereas ephedrine also stimulates alpha receptors as well.
albuterol is the fastest acting, ephedrine is in the middle, and clen is relatively long lasting.
clinically, albuterol has shown a lot of promise as a fat burner. but if you're looking for a "feeling" from it, then you need to look elsewhere. i felt very little from albuterol (or clen, for that matter), but have a significant effect from ephedrine.
another issue that comes up with beta agonists, is they have rapid desensitization. one can easily circumvent this by adding in ketotifen at night. (side note: people often do 2 weeks on, and 2 weeks off for this reason as well. but don't cycle between 2 beta agonists as that defeats the purpose. a better choice would be yohombine in the "off" weeks)
^this issue is largely with clen (vs ephedrine and albuterol), since the half-life is 36 hours (vs 4 or 6 hours).
below is a link with further reading on the subject: