I just realized I hadn't starred most of David's courses. Not sure what happened there - Possibly that I intended to go back and try and finish them as almost all of them a re too hard for me. 
Anyway, all starred now.
Thanks for the stars! All right, started with 1-7 and 1-8 to return the favor.
First one's okay. Only death was those thwomps at the beginning. A bit too high to prepare for, especially in a sky level and after jumping up from a lower place like that. Also felt a little empty overall.
More gotcha thwomps in the second one too, if you take the low route. Grrr, I say. But hurrah for multiple routes.
e: Also 1-1 is a little tedious and not exactly an intro level. Maybe put the koopas in pipes cause the player needs them so much and take the piranhas out of pipes so the bastards stop hiding.
3-1's a little better put together, you're getting better.
There, we're both in the koopa medal club.