I personally like the Drobo. Probably not enough to buy one, simply because it's at a price range where you start to wonder. Couple of reasons why I like it:
1) It's quiet
2) Manufacturer and size dont matter, just pop in a drive and then it takes over and let's you know when it's ready.
3) Easy-to-read "meter" explaining how much space is left
4) A lot of the problems with external enclosures is the heat/power/and interface...oddly, the ONLY three parts that make up a darn enclosure. Drobo perfected all of these 3.
5) I asked my father to bring a HDD over during Thanksgiving so that I could give him some movies. The HDD wouldn't spin up correctly in an external enclosure. Windows wouldn't read/write to it properly. Linux didn't even see it. I tried and tried. (placing it inside the PC rather than in it's enclosure, etc). I figured, bunk drive. My father took it home... same exact results. It was hard to part ways with a 1TB drive so he called me up and I said... "Well, time to break out SpinRite", he said that he wanted to try 1 more thing before that. So, he puts it in his Drobo and starts laughing histerically because the Drobo recognized it right away and starting buzzing/churring away ... It's still in there, every bit of it is recognized... lol. So, he found a new home for it.
6) I like the fact that it has its own proprietary raid array. They say "It's like a RAID5 but not" And i've never seen it lose any data. My father had one of the 4 go down inside and then pop in another drive. a little while later everything was still there.
7) It's pleasant to look at. It's not some bulky tower.
I don't know... perhaps I would have a whole slu of ideas and reasons why I wouldn't like it if I owned one. But, I don't ...
Ya see, I really don't hate everything.