RE: cermark su-31
We have one at our field. It has been flown with an MDS 1.48 and an Irvine 1.50. In both cases the wing loading was a bit high for really good aerobatics and the landing speed was high.
The G-26 weighs maybe a pound more than the Irvine? Plus tail weight to get it to balance. You're looking at a flying brick.
Jim