Around 2 hours 23 minutes to beat. I beat the first 3 stages back to back and then the last 6 stages were done in the stage select in a mixed order. I ended up finishing stage 5 last since it was by far the hardest, taking over an hour I believe. Stage 6 was the second hardest. I will post up both edited and unedited runs to show the process. Even when I got to the end I would often crash into the finishing gate. You have to hit it just right. You cant use the far edges of the screen even though it looks like you should, you die in one hit and there is another ship that tries to bump you into shit. The game also moves very fast on some of the later stages. Each stage has to be done on a single life with no checkpoints.
Deaths were edited out for this version of the playthrough. Check out the unedited playthrough here: