Good work. Apart from the fitness improvement, I think that working on getting the reps evenly paced whilst working hard will also translate to helping with 5k/parkrun pacing. You get a better feel for how much you can afford to let it hurt whilst still maintaining the pace. On the other hand, don't get too tempted to "race" the last rep, as you want to keep good form all the way through.
Good work. Apart from the fitness improvement, I think that working on getting the reps evenly paced whilst working hard will also translate to helping with 5k/parkrun pacing. You get a better feel for how much you can afford to let it hurt whilst still maintaining the pace. On the other hand, don't get too tempted to "race" the last rep, as you want to keep good form all the way through.