My basic £150 model saved my bacon & my 'plane in less than Sunlit VMC on the way to the LAA Rally on the Friday.
That's when it really counts, it's already paid for itself many times over.
As for 'scale', the AWARE display chart is exactly the same size as the std. 1/2mill. paper version. So hardly any problem there !
Even in basic form the nav. capability is stupendous.
I should think if you've money and space for the bigger 7" screen, go for it.
Free airspace (& software) updates from an English company that responds to individual clients has to be hard to beat for quality at an unbeatable price.
mikehallam.
p.s.[A small card 'eyebrow' takes the edge off very bright Sun].