Basically V3 is better than V2 in every way (from measurement and listening test). So regardless of the model that you have (SE or not), the improvement will show. Does it mean that the 9V3 could sound better than 9V2SE? We haven't done the direct comparison, but most likely (similarly, 9V2 outperforms 9V1SE). Obviously 9V3SE will achieve the next level of performance at all frequency range, clarity, resolution, dynamic.
What about power increase? V2 to V3 is an amplifier improvement, not power (slight improvement on 4 ohm load). But this new amp board will benefit from future power supply improvement. Since Nuforce amp has been widely used worldwide with many speakers and there hasn't been much complain about lack of power, we decided to focus on amp board improvement.
Upgrade => directly replacement of existing module, no change of appearance.
Trade-in => change of product. It is obvious that you can't upgrade from a 8.5" wide chassis to the 17" wide Ref 18 so that will be a trade-in. We make a pledge to provide upgrade path but there is no guarantee for trade-in. It is too early to discuss trade-in for Ref 18 because we have not even determine on the performance of Ref 18. We can't sell something with higher price without good justification for it.