Hi Oman,
There's photos of the 2 readers side by side at:
https://www.mobileread.com/forums/showthread.php?t=52682
Mneme did a great review of the V5 at:
https://www.mobileread.com/forums/showthread.php?t=55228
There's several people at Mobileread who have bought an ECO Reader or HanLin V5 from DA after they've purchased a different device from us.
DA supports the manufacturers' warranties and offers technical help for all the ebook readers we sell.
You may also be interested in this thread:
https://www.mobileread.com/forums/showthread.php?t=52769
We released the ECO Reader just over a month ago and we've made a commitment to supply and support them. We'll also supply ebooks for them via our (pending) ebook store.
We released the HanLin V5 even more recently.
They're not going to be obsolete/unsupported in the near future.
But... as I mentioned earlier in this thread, there's many changes/enhancements coming. You can choose your device now with its current functionality or wait and see what's coming up next.