I use the Heiland Splitgrade on a Kienzle 6x9 since 2004 with the motor driven filter module. As mentionned above, have a look at their webpage http://www.heilandelectronic.de/ to get a detailled description. The system is very easy to use.
The grade and the time measured by the splitgrade for a given paper is a very good starting point. Up to you to interpret these parameters to get the result you want to have. I would not like to miss it in my darkroom.
And not to forget, Mr Heiland is a very helpful person who will give you all the
information you need. Don't hesitate to contact him.