I favour like this so side by side but with a gap between for clarity. It does mean they’re smaller but it’s only to give an impression of the item to them click through to if you like it so that suits me fine but it really is just personal preference so whatever you favour stick with.
I like that you’re giving a front and back view though, that’s a good idea.
I’m less structured than @Ian_Chimp though so just post the normal 200x265 size and reduce by a percentage to fit 
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Do mine fit side by side on your phone Mr Chimp?