Macro for Oly 14-150: MCON-P01 or Canon 500D or Canon 250D?

I'm looking for a higher grade of macro adapter for the Olympus 14-150. Tested the MCON-P01. My refurb copy was delivered in poor condition so it is going back. It is plastic and feels fragile. Normally I do not object to plastic as modern synthetics can be very durable. However, in this case, I'm not a f an of plastic elements (if it is) and the body is simply way too thin.

So now I'm looking at the Canon 500D or 250D lens - they do cost more but have metal ring, glass elements, and two elements.

Question: Would the 500D give similar sized magnification as the MCON-P01? or should I go for the 250D?

Appreciate any informed comments.

Thanks,

MTMT