I have been using Funn Mambas for a few years. Being an “older” rider , I do like my feet not clipped in when doing steeps / rough/ rooty stuff …
However long uphills etc are better clipped in.
The Mambas work well generally – but SPD platform is not recessed, so you have to really ride that side clipped in ( as you would) – but they do not clip in a smoothly as shim offerings.
Riding on the flat side – with SPD cleat on, so when you do not want to be cleated in, does tend to chuff up the pedals finish quickly – so they end up scarred.
But they have been resilient – so I would recommend
That said, I have just changed over to dome DMR V12s, as I am using SPD less and less. Ging balls out fast is really a huge issue.