Just wanted to add, I tend to tether my S2 naked, no case, as the case just adds more weight. So I have the plates attached to the back of the S2, and tape (gaffers) the kickstand closed. So far no problems.
I do this because in Arkansas, heat and humidity are bad 6 to 7 months a year, the case adds just another layer to get hot and and it's black. (at least mine is). Allowing the S2 to be totally exposed just keeps it cooler. I use a sleeve (again from Ken) that I keep the S2 in during travel. The case fan on the S3 will come on pretty quickly, unlike the S2, which can take a bit more heat or so it seems.
I still use the S2 for my work as the S3 (I have the i5 with 8GB) seems to get hotter and mine does not have as good a battery life as the S2. But mostly because my tired older eyes hate that tight resolution on the S3 screen, just hard to read for me. The S2 is perfect in that regard. I also feel I have less glare issues with the S2 than the S3. Glare is the real killer but with the clamps you can use the S2/S3 on the tripod leg, and then pop it off for a look with the longer USB3 cable, and turn away from the sun to get away from the glare.
Is it all worth it, to me yes. As a tech camera user, I get eye strain looking at the IQ screen at 100% all day long. Yes it's a great screen still best in the field IMO, but still small. Tethered, you have the image at 100% instantly, and with the nav window (as a floating tool), can move around the file quickly. You can also apply some highlight reduction or shadow push in C1 to see if you have pulled too much noise in shadows or blown a critical highlight. However the 100% view on the much larger S2/S3 screen for focus check is the main benefit to me.
My only issue, I sure wish Phase One will allow dual writes, i.e. to the card and PC but so far that has not been made possible, (not sure why it can't be done).
Paul
