Don, in Austria it is possible to order the igus parts in every length you want them to be, up to 400 cm I think. You pay a little bit for that - but maybe that is not possible in the states if you order them from Amazon.com.
Same findings here: I used the white balance automatic when shooting on the sea some sea-lions - and ended up with a terrible difference in the colors. Ok, can be corrected in the post, but I have also learned that it is a nice idea to work with fixed white balance. And sequential serial numbers are great! That makes it very very likely that the optical and sync drift behaviour is very similar.
Sure, with 60p the difference between frames is small. But I would tend to use such a controller if possible, since they allow to see if the readout from the chip starts synchrone. That is something different what Don mentions. The start point of recording
of the two AVCHD cameras when you start to shoot differs always by something like 0-4 frames, I think it is because we are talking about consumer cameras here and not a professional Genlock. The difference in the start point of recording has to be adjusted in the postpro, what can be done in Vegas in a nice way. And yes, for the synchronisation - so the differene in start of recording - I have purchased a clicker. Cheap nice solution, you know such a part that they use for pet trainings, and that makes it easier to see the correct point in wave form in the timeline.
But even if one camera starts 3 or 4 frames later, the second question is if the startpoint of the readout of the chips
of both cameras is similar. Without that, it may happen that one camera starts at line zeor, while the other is in the mid of the chip. A difference in startpoint of readout of the CMOS chips is smaller then the startpoint of recording - at the worst it is the length of a frame, sure. BUT you never ever can correct that again, if you have not got that right during shooting. That is why it makes sense to use controller for the sync drift, to see where you are.
I use a ste-fra lance, but it is not cheaper really: http://www.digi-dat.de/produkte/index_eng.html#stefraLANC
For sure, with 50p or 60p it is less worse compared with 24 or 25p. And if your motives tend to be static, it is less an issue. I understood it is expensive at Brazil.
My question was more about the playback behaviour of two 1080 60p clips, not about rendering. With two 1080 50p clips I see with my i7 2600K 4.4. Ghz and 16 GB ram a dropdown in the preview speed to something about 30-40 fps (100% would be 50 fps), with preview settings at "preview/full". We had the idea to the the project to 720 50p or 720 60p to overcome that, what works fine in Vegas too. Sure, you also could go to "preview/half resolution" in the preview.
Another question: how satisfied are you with the mechanical adjustment of the rig? Do you see a strong difference in vertical adjustment, rotation, keystone, zoom?