A compressed LTO6 is 6.25 TB, right? Let's just go with 3 of them.
So, I figured out how many carts we need. You calculate the fractional station wagon part. My math was never _that_ good ;-)
That is likely to be cheaper than a 16 TB SSD for a very long time to come. Tapes aren't going anywhere.
Hopefully we'll see LTO-7 this year but probably in 2016. That puts the diff between LTO6 and LTO7 at 4 years.
Extrapolating... LTO8 in 2020 LTO9 in 2024 LTO10 in 2028
LTO-10 would have ideally come in 2020 in keeping with LTO's earlier pace of 2 years per revision which is also more in line with storage increases
I'm off to research the weight differences, and see if the wagon's suspension factors in to this...