I used aspen for a while now, supply is almost out, would like to switch to something new

What is the preferred substrate, This will be for my Boa and BP's

Repti-bark
Forest Floor
Eco Earth
or a combination of the above??

any opinions on those or one I haven't mentioned??

@Bogertophis I believe you have said you use Carefresh bedding? Though I could be wrong

I ended up with a few bags of the brown natural Carefresh bedding I was going to use for my Corn snake. I guessing that would be safe and he would like to be able to burrow around in it?
He burrows in the Aspen now, but ends up matting it down and I have to fluff it up now and then so he can burrow again

Thanks in advance for any advice!