I agree with most of the above but, in the case of the C150, 40 degrees of flap is excessive for most landing situations and can get the infrequent flyer into trouble, which is why Cessna limited the setting to 30 degrees on the 152. It's satisfying to carry out a short field landing into wind with 40 degrees and stop in a matter of feet but it's a technique which requires constant practice. 30 degrees has sufficient drag to give a sensible landing run on most runways - a short stop followed by a long taxy to the next turn-off won't endear you to the tower if there's traffic backed up behind you on finals. Obviously, we all need to keep proficient in short-field technique because tomorrow might just be the day we head down into that meadow with the engine stopped.