For what it's worth, I've owned several of the original model and have been using 2 of the new ones for the last month or so. I've had no problems totally replacing the old ones with the new ones in my workflow, and I absolutely love the new cable locks. One tip that may help folks here that are newer to these boxes is that you always need to switch the frame rate on the tentacle to the proper setting before attempting to jam. I don't believe they will auto-jam and pick the right frame rate by themselves. This is one of the reasons I have enjoyed using the newer ones - being able to do this wirelessly.
I have had no problems with mine doing this. Jamming from a 633, have used to feed C300, C500, Amira, Alexa, Mini, various Reds, FS7, F5, probably some Ursa models, etc.