Encoders from Wirz

I found: @ http://wirz.com/surplus/index.html
QUBE Encoders from Danaher Controls
We have a very limited supply of these high qualtity incremental
industrial encoders from Danaher Controls,Model# 320120300000. The
encoders use a magnetic technology with a 120 ppr TTL current sink
quadatureoutput. The 1/4" x 3/4" shaft is on ABEC precison bearings with
30 lb axial load rating. Data sheet included.$25.00, similar units sold
in industrial magazines for over $200.

Are these going to be suitable for our servo systems? Those who know,
Let me know, and Save me three!