Interesting the HTHS is higher for the 5W-30 than the 5W-20. Must not shear-stretch in the journal bearings? Since OCI's are shorter for GDI engines, I'd think about going with the 5W-30.
Even if 5W-30 does permanently shear in the power cylinder / valve train HTFS areas, the resultant sheared junk gets drained with the OCI. Worst case you end up with a 5W-20 by a 5,000 mile OCI.