That is prob a 32 bit limit of Raspbian at a guess.
The Odriod C2 is prob a good one, but I found its all circular as 64bit, USB 3.0, 2GB ram (4GB prefer) just doesn't exist at a good price.
There is a current rake of great hardware that is so perfect and its all going into phones and TV boxes and one of them soon is going to end up as a maker board somewhere between £40 - £90 quid.
I have decided to play and see how software Raid plays with a Sata port multiplier on my I5 running Ubuntu.
Then when I get one of those boards or maybe it might actually be a rom swap on a tv-box to name drop rk3399 once more I will have some comparison.
Odroid C2 is prob good for a singular USB external and a good package, but for me is very close, but just short of a sweet spot.
If haven't read it https://forum.owncloud.org/viewtopic.php?f=17&t=7733
So dunno but, yeah I had a Pi3 before the interest in Owncloud and wouldn't even bother, but we all have different criteria.
I like the Pi3 but to be honest when it comes to I/O it kind of sucks.
I keep going on about the RK3399 and I have a hunch it will end up like the RK3188 that eventually is a sea of cheap Chinese clones.
Might be wishful thinking but actually I am betting its just a matter of time, how long is harder to say.
Currently if you do some reading about the Sata II interfaces they are processor limited and have some sort of problem that limits write speed.
After looking for a while USB 3.0 seemed a better idea.
Then struggled to find a 64 bit platform... Circles again.
Just to be an early adopter with my makers head, I am prepared to spend £80 -£100.
I am expecting them to maybe end up as low as £50.
I am going to play with BTRFS RAID5 as its really interesting because of the way BTRFS works as only the disk needs to be resynced and not the whole volume.
RAID5 is still experimental with BTRFS and there are probs on resync, but its getting very close to complete and thought I would try and track down where it is at.
RAID5 is generally depreciated because of the need to resync a whole volume and the chance it possible to have another disk failure in that resync.
But I am presuming because of the way BTRFS shares chunks and the need to only resync the missing disk, BTRFS changes the game on RAID5 if they can iron out the bugs.
But its just my makers head and hobbyist playing, but its very possible with a small Li backup to create a scenario to write out the buffers and cache and that solves another problem with current BTRFS RAID5 apart from system crashes.