I’m a fan of clipless pedals but on my folding bikes I sometimes want flat pedals & for travel/transport I want the bike compact. To me, the MKS removable pedals have filled the bill. I have flat & clipless pedals that are the “pre-Superior” models (the Superior model uses an adapter that has an improved locking device but there isn’t a clipless model & the adapters aren’t compatible with the earlier adapters). For the clipless pedals, you need to use the MKS cleats for your shoes & these are compatible with both MKS & Shimano clipless pedals (ie the Shimano cleat is not compatible with the MKS clipless pedal).
MKS provide a yellow nylon circlip for the non-Superior removable pedals, as a safety locking device for ensuring the pedals don’t unexpectedly disconnect from the adapters. To me they are a nuisance & slow down the removal of the pedals when necessary. For the clipless pedals they hardly seem worthwhile because your shoe is locked to the pedal, but on the flat pedals a soft-soled trainer-type shoe is broader & may come in contact with the adapter (& possibly release the pedal). My solution was to fabricate an alloy plate to bolt to the adapter end of the flat pedal, ensuring that any shoe cannot come in contact with the adapter (see pic).
When Ralph came along, I noticed that the front tyre can release the right side clipless pedal when Ralph is folded (it seems to be a factor of the widened frame & the Kojak tyres (see pic). As I don’t often have to remove the right side pedal, I’ve fitted the MKS circlip on that side.