From what I remember, when I did 23andme, you could opt out from being found. Honestly, I think that the best option is to use the cheapest service that sends you the raw data and then dig deeper into it using Promethease or other service/software, especially if you just want to check for SNPs and health related information. 23andme is quite limited. Though I haven’t tried MyHeritage.
Also, 23andme is quite unspecific for non-European ethnicities. I’m mixed, and for the Italian part, it gives me very specific information, even the regions and cities of my ancestors:
But for the “Chilean” part, it just highlights the whole American continent and shows me this:
Which is kind of useless because I was born in Santiago and most Chilean-Italians arrived through the port in Buenos Aires, so nothing I didn’t know 
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