general pest erradication

[jkhom]

I occasionally notice signs of pests on my orchids. I've had spider mites, occasionally I see snails (about 1/16" shell), and yesterday I saw a little flying insect that was silver/white and about the size of a misquito sucking on a leaf. Usually I don't actually see the pests, just the tell tale signs like little brown dots on the leaves of the small webs.
To get rid of these pests, should I get insecticidal soap or should I use neem oil? Which is safer for the plants? Plants are indoors under lights if that makes a difference.
Thanks for your help.