i'd go with cypress for both, but aspen is perfectly fine for carpets... aspen doesn't do as well with humidity though, so far gtp's and some other morelia i'd stay away.
Colin Vestrand
long time keeper and breeder of carpet pythons and other snakes...
i've been using cypress or newspaper for a while and was hoping to get everything on aspen if possible. im sure i can keep humidity up with the aspen shavings but i heard it mentioned before that because aspen is so dusty its not the best thing for GTPs.
Aspen will work for the carpets but I would keep it away from the GTP's. Aspen tends to dry the air and can become moldy if it gets too wet trying to hold humidity.