The main reason I still use my Archos devices is that they've got this huge amount of local storage. The problem is, this is not what our "technical suppliers" want to push right now. The "official party line" is no longer "local storage" but rather going back to the old 1970s style of computing, with "dumb terminals" being served data from a centralized server. They've renamed it "the Cloud" and thus it's "trendy" but ultimately, it's the same concept from way back then. It's nothing new.
Seagate has been offering a very-high-capacity, very-low-power-draw hard disk which would be perfect for the sort of device you (and I) are looking for, but nobody is making use of it at the moment. It's really disappointing.
Yes, IF I could buy a device with 500GB to 3TB of onboard local storage, running an up-to-date OS on up-to-date hardware, I'd be a very, very happy guy.
But, at the moment, nobody is inclined to make a device like that, so we're both out of luck.
And thus, I keep my original Generation 6 Archos 5IMT (250GB), and my original Generation 7 Archos 5IT (500GB), and have purchased another one of those 500GB units, "used but barely touched" off of ebay, along with two 16GB and an 8GB (supposedly) "nonfunctional" but easily fixed by me... one of which was used for parts to be able to repair my original 500GB, whose battery charger controller PCB had fried.
So, I have five FUNCTIONAL Archos 5 devices... three of which are "large storage" (and heavy) and two of which are light, slim, and still have as much capacity as many devices CURRENTLY being sold.
If you really want to have large storage available with a modern device, you'll have to get an external HD to connect to your device (via USB or via wireless)... there are several available... or you'll have to put your data on a server and use a lot of wireless data to stream your content to your device.
Of course, if you're someplace without wireless, or if wireless costs you a lot, this latter option is no option at all, really. So... for me, the 500GB device is my "geeky toy of choice" when away from home, and the 16GB one is the one I use at home (where I can stream from my home server over my home network).
I'm still hoping that someone will come up with an up-to-date version of a 5"-ish large-storage tablet (or phone)... but so far, no such luck. And it's becoming more of an issue all the time, as the browser in the Archos 5IT is no longer up-to-date with the internet standards and can't display 2 out of three pages I go to these days, it seems.