That's what I'd recommend, but I think the marketing for these makes them seem more durable than they are. Mine wasn't completely water tight either, but my DS 150 is. Just something to be aware of.
Don't stand on them then, get a stool?
Best tool boxes I've found, but beware of standing on them. Was fine for a bit and then suddenly one of the honeycomb supports on the inside of the lid cracked. Exterior is fine but now it bows a bit when stood on. Basically don't stand on them, as they're not as tough as made out to be.
"You can buy here on our website At partshopdirect.co.uk or you can collect in person from our shop in the heart of Liverpool City Centre. We are Service ..." also free delivery on orders over £60 (this is regarding the tray discussed in the comments)