When I owned the SD7, I also owned the SD 1000 plus. Same sound engine less the Ram sounds.
I also owned the Integra7..

These comments are based on sound and not the features.

At this same period of time I also had the G70, BK9, and EA7.

The following are my observations..

The drums and basses on both Ketrons (SD7 and SD1000+) are a given.
They sound real.
The G70 with Studio exp, come close to Ketron.
BK9 a bit better than G70 (bass and drums).
Followed by the EA7.

But I found (not surprising) Integra7 (Supernatural), the best of all.

If I had to choose the sound device again. It would be along the same lines as before. I would use the Integra7 (sounds), and need a keyboard to use (G70).

I love some of the features on SD7, I also dislike what it does not do. I would not replace the G70 with the SD7.

If you want that Ketron sound.. go for SD1000+

If you want the best sound device ever..Integra7.