Installing chipsets, Mass Storages and USB drivers this way worked well, but added a painful 3-4 minutes to startup I reverted to integrated method. This seems good for Network, Wifi, video and other stuff. And Startup speed is much better.
Anyway, SSTR approach can co-exist with integrated drivers. SSTR external folder can be left INF-empty and pecmd.ini processing will happily continue (I think userdrivers.cmd would benefit from an IF statemement checking also for *existing* INF files before starting the pnputil command). This way you can have your integrated driver pack, but can also drop anything chipset/storage/usb-related (or other) in the external folder and stay covered.Finally according to your tests, do you mean that SSTR external (and uncompressed) folder is faster for video/lan/wifi/other, than the DEVI $CAB command set?
Maybe you consider creating a package including pecmd.exe which starts with pecmd_malok.cmd --> that starts pecmd.exe with ini etc. etc.
This plugin demonstrate the method explained...