Although not necessarily a fan of the Rockwell distribution block because of its size, we had no complaints about its performance. We followed the manufacturers directions regarding wire prep. All inbound wires were secured with strain reliefs. We used wires of the appropriate gauge size, and left the ends loose (unsoldered). As a result, we never had a problem with wires working loose from the block during the entire season. We checked the clamp screws periodically to see if there was an issue, but found that they never worked loose and did not need to be retightened.
Although I have not had a chance to play with one yet (c'mon, when are they going to announce who is in the beta test program?
), I expect that the 2009 distribution block will perform just as well if reasonable care is taken to use it properly. Follow the manufacturers recommendations, use the correct wire size, tie down all wires properly (this is a VERY important step - anticipate that wire bundles will be vibrating and shaking, and apply appropriate countermeasures to minimize the transmitted forces), tighten everything to spec, and I suspect that you won't see a whole lot of problems.
-dave
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