upgrading RAM mac mini (mid 2011)

I have a Mac mini (mid 2011): 2,5 GHz Intel Core i5 with 4 (2x2) GB 1333MHz DDR3 RAM.

I want to upgrade RAM: I could buy 2 x 4 GB Kingston 1333MHz RAM, then I would have 8.
Can I also buy 1 x 8 GB Kingston 1333MHz RAM and have 10 GB (original 2 GB + new 8 GB) RAM? If the type DDR3 and Clockspeed 1333 MHz match is that sufficient? Or is that not recommended? If so, why not?

thank you

It's not just a matter of matching the Clockspeed and ensuring that it's DDR3 that matters, but there are other characteristics of the RAM that matter as well.

We strongly recommend sticking with vendors like OWC, Crucial or Micron that have a nice selection option to show you exactly what will work with your Mac Mini..

OWC, for example, has the following offering for your Mac Mini..

You could purchase just the single 8GB stick from them and use an existing 2GB to get a 10GB total.

and Kingston is not good? The webshop in my country doesn't offer OWC and I am not going to order it from across the Atlantic. It does have Crucial, but they haven't got as many favorable reviews as Kingston.

Kingston is fine too, what I would suggest that is you look at all the specs of the compatible RAM from OWC/Crucial/Micron and then match it up as much as you can for the Kingston..

Ooops. According to Apple's specs for Mac mini 2011, it will only accept modules of 1, 2 or 4 GB. So I will have to buy 2 x 4 GB.

Apple always seem to indicate that a particular Mac supports less RAM that it really does, EveryMac suggests that you can actually go up to 16GB with 8GBx2, so your plan to get a single 8GB should be fine as well..