I just got the GENUSTECH Canon C300 / C500 Top Handle.
This solves a lot of fixture needs for me ! (screw and 15mm rod support)
Build quality is great and it sits thighter then the stock grip which was always a bit loose.
Still not a 100% thight fit, but buch better. A fixture screw like the one on the original handle would have been nice, as you’ll need either a very short or a full size screwdrive to attach it to the body.
After a short usage I really recomend this grip, which comes for a great price !
Shipment was also very fast. Ordered it on wednesday, received it in Switzerland on monday :o)
Let me know if you got any questions.
UPDATE:
The GENUSTECH Top Handle is a tiny bit lower (7cm comapared to about 7.5cm) and runs horizontal, while the original handle slightly raises.
Another difference is the original runs forward and the GENUSTECH backwards. So hand placement is different.
Someone asked me if it would be possible to add the original one on top. This is not possible due of the design in the shoe area. You can’t get it on. But certainly you could go with the GENUSTECH on top of the original one.