Last time it was £219, so I'd guess the £199 offer is done and dusted. It'll likely be back at some stage for £219.
Tool storage seems to be big business, judging by some of the prices charged for bags/boxes etc. No way would I give £179 for that Klein trolley bag - not enough storage space for the money. Not sure how good Dewalt's Tough System is, but I'd sooner give £20 less for the vastly greater capacity it offers.
I think you are right. The CK bag looks okay. Plenty of room for tools. I think the problem I have at the moment is whilst I’m doing my apprenticeship I’m always with someone. It’s dependant on them having the room in their van to load a trolley. This is we’re the CK bag makes a little sense. So there is that to consider.