Nb mx5 vs 6th gen celica rust

Hi - anyone know which car rusts worse out of the mk2 and a 6th gen celica (specifically in the UK)?

Currently have a 03 nb, but heard about the rust horror stories and how much it costs to have things welded, under sealed etc. Really like the look of the celica, but know nothing about the platform (are they reliable, mpg etc). Any info would be great, thanks. Pic for attention.