I have had wellgo V8 copies, some “Grey” CNC jobbies, two pairs of MG1s and a pair of Nanos.
I recommend the nanos highest. Do the job, the low-profile nature of them is great, decent weight and they are resilient.
I do NOT recommend MG1s. I have one wellgo badged pair and one Onza badged pair (Onza Hognesium). Both suffer from chronic pin loss – what happens is when they get bashed on rocks (common enough occurrence on Peak District rock gardens) the pin gets smashed out of the pedal. However, as the pin is made of steel that is much much harder than the magnesium that the pedal is cast from, the pin shears out taking any semblance of thread and usually a decent chunk of metal along with it. You can replace them by cleaning out the hole and putting a new pin in and setting the base of the pin (and filling the remainder of the hole) with JB Weld, ending up with a 1-2mm high dome of JB weld around the pin above the metal of the pedal frame. Anyway, the point is that MG1s are not as resilient as nanos. Lots of people will say that they’ve used their MG1s for ages with no problem and that’s fine – my own pairs have lost about 10 pins between them due to this problem.
I don’t find the two particularly different in terms of grip (using 5-10s), but I imagine that it will depend also on how big your feet are. Nanos have a bigger platform than MG1s.