A poster on another forum was comparing the standalone EI's to Surefly and Pmag's. His comment was similar and that the complexity of SDS and EFII was greater.
After thinking about it, I would only agree that they are more complex to install, and visually more complex looking. All the components in SDS or EFII, also exist in Surefly and Pmags. Plus the Surefly and Pmags are mechanically driven, with items to wear out and break. The MAP's and ECU's are built into the case of the Pmags/Surefly, but they are just as complex. All the complexity of the Pmags are also mounted to a hot, vibrating engine, where the complexity of the SDS/EFII is shock mounted on the cold side of the firewall.
Each has a magnetic trigger, MAP, and ECU that run the ignition. SDS/EFII have a more complicated install. Surefly/Pmag have mechanical components to wear out/fail, and their sensitive electronics are mounted in a more hostile environment.
Take your pick. I went with the full standalone EFI/EI. The only wear items are a couple of electric pumps that cost 100 bucks to replace. No other moving parts other than a couple of magnets spinning around on the flywheel.
I have nothing against the EI mag replacements at all, just the opposite. They are a very simple, elegant replacement for mags. I don't believe they are technically simpler from a systems design standpoint. Only from an installation point of view.