I have learned a lot in using the DYN-G for 3 years now. I have a few things to say about it:
Many problems with the DYN-G might be related to its impedence. The DYN-G has a medium impedence, which means the signal will not lose quality for up to a length of 40-feet. The Schertler amps can deliver a lower 10v signal to the DYN-G pickup, which makes their amps a perfect companion to the DYN-G. If you plug a Schertler DYN-G into a 48v jack, the pickup probably will have a higher potential for feedback than if you plugged it into a 10v or a 0v jack.
Also, to avoid feedback with a Schertler DYN-G you sometimes will need to angle your guitars top so that it is parallel to the speaker of your amp. I noticed this when using the Crate battery amp. For this reason, if you and another guitar player are BOTH using a DYN-G through a Schertler UNICO, you will get feedback because of 2 reasons:
1. One of you is plugged into the 10v jack and the other is plugged into the 48v jack. To solve this, get a 1/4" adaptor and plug the second DYN-G into the 10v 1/4" jack. This way, they are both getting 10v.
2. While one of you can angle the guitar to the no-feedback angle, the other player invariably probably cannot and in turn that will give a environment ripe for feedback.
Also, Schertlers are not really meant to be EQ'd . The UNICO amps have EQ on them and I would say its ok to use that but the frequency response of the pickup is generally flat (in the range of 60 to 18kHz) and adjusting EQ has a different effect on this pickup than it would on a MIC or some other pickup system. The UNICO has a Resonance filter that I think makes the simple EQ more powerful.
By the way, I think a Bigtone also sounds beautiful through a Schertler UNICO. Just my opinion.
If anyone has any other thoughts, or if you want to tell me I am full of it, please add.