I did a 8" Aspen last fall with the SOD... It still gave me a little workout and that was after me sharpening it, but it improved the results 10 fold from when I first recieved it...even still the SOD has still been my choice as my main type of survival type blade stashed away with other gear ready for D-day ......I would imagine they would be similar in chopping using the Kenetic Energy scale. Speedxspeed x weight / 42xxxx. If the grindheight is different ..or further up (flatter) I'd give the edge to the regulator.... Even being made of different steels the SR77 has shown excellent results for me vs wood and really never had an issue with lots of wood so I think only geometry will be the only key player with the REG and SOD heads up challenge.