In article ,
wrote:
I'd never use DGfets for something like a scope amp or other
instrumentation where DC operating point or balance is a
requirement.

Interestingly enough, in Jim Williams's book "The Art and Science of
Analog Circuit Design", there's a chapter by Steve Roach of Tektronix,
which shows the use of a BF996 consumer-grade dual gate FET in a 1GHz
oscilloscope preamp.

http://books.google.com/books?vid=IS...VGMx8v3yDD4at4