This is the Verge's big win here - somehow people believe that the Apple Watch is laggy.
The Apple Watch OS is fluid and there is no lag. The only lag you will get is when using 3rd party apps, and this is because of Apple's decision to handle all the 3rd party app processing on the iPhone, and the iPhone tells the watch what to do over bluetooth. It has nothing to do with the speed of the Watch OS processor, it really has to do with Apple's initial concern over developers writing apps which drain the Watch's battery.
So place your 'concern' over the battery, not the processor or GUI.
I'll wait to the 24th to make that judgement. A number of reviews hinted at lag, or slow responses , even when lifting the watch , and waiting for the screen to turn on. The units in store were demo units, not retail versions, so yet again they did not give a true indication. Sorry but you do not have proof that there is no lag, I think you want it to be awesome, but frankly we need to see how it performs once we recieve ours. Saying its the 3rd party apps that have lag, my iphone would suck if non Apple apps were lagging . Fundementally apple produced a device with a very poor battery resulting consequences? So maybe the score given by some reviewers is justified.