Hi Mark, whichever unit you go for find out how easy it is to get replacement parts if/when required before you buy.
I bought a Britool box three years ago and spend the last two years trying to get replacement drawer slides as they skimped on the build and only put one slide on a large drawer built for two slides.Each and every part has a part no on it but they dont recognise the no's as they have 4/5 different companies who build the boxes but cant tell who's part no's they are.
Moral of the story, only buy boxes/cabinates from a company who make there own and can supply parts when required.
Hth Sean