I would recommend a very old school approach:

- Buy as many SP and U-Matic play only decks that you can find that work and will play, not record. UMatic is dirt cheap, and SP is right next to it for a play deck. 

- Set up some old Windows XP systems. Think 5 years old CPU speed. DualCore. 

- Get your hands on the same number of Canopus DV Storm2 Cards; hard to find. - WHY?  The DV Storm2 Cards allow 1 Computer to capture simultaneously three (3) streams of SD quality video 480i (Same standard as both SP and U-Matic); and will on the fly, compress it to DV Codec. Which is 12 GB per Hour of footage. 

- This was years ago (although the systems are still sitting in a closet); we had 6 of these systems set up, each with 3 MiniDV Players.  So we could capture the footage at 6x3= 18 normal speed. Hand us 18 hours of tape, 1 hour to capture. All to a networked hard drive. 

- Now you will need 1 additional part; SP / U Matic will not have firewire out. Which is all the Canopus DVStorm2 will accept if you want 3 capture streams at once... But place in an analog to FW BlackMagic converter box ($300) on each output... and you're in business. 

The capture quality on the Canopus cards is fantastic (for SD/DV). But the fact that if you use the above setup; you could get up and running for a very low cost:

(6) Dell XPS Workstations @ $300 Each. XP OS. 
(6) Canopus DVStorm2 Cards with the Add on Canopus Breakout Bay giving you (3) inputs.   Pricing... hard to find. Very.
(18) Black Magic Adapters @ $300 Each
(18) Decks @ $300 Average Price considering UMatic should be free. 

$12,600 total cost not including the DVStorm Cards, which when available can go for a few hundred to a thousand. Depending on if theres a buyer. 

27,000 Hours of tape, if you hand feed the decks, keep them running in 2 shifts, 15 hours a day = 15 x 18 = 270 Hours a Day Captured. Add a third Shift: 396 Hours a Day. 

Youll need rewinders, or extra decks to keep things moving. But thats what I would do. 

Low cost, high output. You could set up 10 systems if you can budget it. But with 6 running 24x7 you could get your capture done 70-80 Days if you stay on it. Double the systems: 30-40 days. 

Hope that helps!