Short review of the Stretch 2x4, keeping in mind that I'm a regular joe, not someone who will push a board to its max. Had it out at least 15 times now, so I feel that I have a handle on it.
Got my 2x4 in 6'6 step up size at 19 3/4 x 2 3/4. Usually I ride medium fins in my step ups but that felt a bit squirrely so I put in large fins (thruster) and that helped. There are some boards that feel like they're the weapon you want for life and death battles. For me that would be the Tank and the Carrera.
The 2x4 feels a bit more loose, like it's not glued to the face. That could be a good thing or bad thing, depending on how you look at it. 2x4 doesn't inspire confidence in critical sections, but it's very fun to do turns on and has a certain glide factor that feels awfully fun in the right moments.
Actually reading Stretch's website, I see that the 2x4 is advertised as more of a daily driver type board, not a step up/semi gun. That makes sense. Not sure why Stretch shaped me this board? I just emailed him and said I wanted a step up and this is what he recommended. Interesting.
Overall thoughts: fun board, look forward to riding it for a long time. Feels a touch uneasy in the heavy sections, but more fun to rip on than a gunny shape. Legacy construction is bullet proof.
Would bang again, as a shortboard. Also, never tried it as a quad. Might give that a go at some point.