Which 12v TV is best?

I expect this is a well-worn topic but we'd love to hear opinons on which of the well-known "traveller" type TVs to buy for our new motorhome:   Avtex (pricey but well-regarded), Cello (much cheaper with mixed reviews), Finlux (likewise)?

LED HD models with built-in DVD players between 18.5 inches and 22 inches sound like the business - but which make is the best?

Where we are, in deepest Devon, it's a long trek to find dealers with all, or even any of them, in stock to actually view before buying.  Seems a bit of a gamble to buy one over the internet without seeing and hearing first!

We'd much appreciate advice and guidance from y'all.