6 top and bottom. 4 perimeter. 0.15mm layers. 99% infill.
http://www.thingiverse.com/thing:104868
And then pulled them apart.


Since there is just one sample of each material, it is not statistically-valid. Ranked from best to worst for this one-non-valid test:
Polymaker Polymax (205C) $77.89 per KG
ColorFabb PLA-PHA (205C) $56.00 per KG
eSun PETG (yellow) (250C) $33.99 per KG
Taulman Tritan (275C) $90.00 per KG
ColorFabb XT (250C) $65.33 per KG
Octave ABS (230C) $31.00 per KG
Not tested yet:
Taulman 645 (245C) $70.40 per KG
GizmoDork Polycarbonate (300C) $49.99 per KG