How can you run out of space with 16TB worth of DroboPro space. Well apparently it isn't so hard with all the home movies and photos I've been taking. I have an old DroboPro with a mix of 3TB and 2TB drives and it is 98% full!
I've tried taking a few things off, but now that one of the drives is red, seems like it is time to see if I should continue with the Seagate 3TB drives I've been buying (fingers crossed, non have died yet!). I'm running in RAID 6 on both my storage devices, so theoretically two need to die for something really bad to happen (heck, since I have a pair, technically, I need to lose 4 of 16 drives :-). But time now to look again and see what is out there. Storagereview.com has been a good performance site and then I use the user reviews of newegg.com and amazon.com to gauge realiability.
Right now the recommendations are:

• For mass storage, there is a finally a set of reasonably priced 4TB drives. The 3TB drives (based on 800GB/platter) are still around at $160, but you can get a 4TB drive for$200 ($180 for the OEM version). Seagate makes one for the desktop, retail is STDB4000400 OEM model is ST4000DM000 (what a name!). It does spin slower at 5900 rpm vs 7200 rpm but still gives 140MBps vs. 160MBps for previous generation 3TB spinning at 7200 rpm, but that makes it great for archival storage (eg NASes). It only has a two year warranty though. • Seagate Momentus XT. This is a 500GB drive with 4GB flast at$130 that is a good compromise hybrid drive for a notebook.
• For a mainstream SSD, the Crucial M500 seems to be the best choice or get a last generation Crucial m4 or Samsung SSD 830 on close out (We have a bunch of Samsung SSD 830s and they are very good). For an older macbook, it probably doesn't much matter what you get as anything is better than a slow hard drive. Kind of amazing speeds with 500MBps read and 400MBps write so something like 5x what you might get out of a traditional hard drive. The Samsung 840 Pro by the way is wicked fast. Crucial M500 (Amazon).