I've been doing a fair bit of failed-engine practice over the last month (PLB in for service, so limited to the local area. Done lots of other exercise too...). Anyhow, two things I discovered.
Shooting glide approaches from anywhere to the strip (on very quiet days so I wasn't disturbing circuit traffic), it's the last 300 ft that really tell you whether it was successful or not. It's a dirty feeling when you find yourself too low to make it when everything seemed hunky-dory. Also, come in from the dead side if there is no one else about. You're not always going to get left hand circuits in an emergency landing.
Go a (known) decent distance away from the strip at a (known) fair height (say 5 miles at 4000' AGL). Glide towards the strip being really careful to maintain best glide. Note where you end up. Now go back and do it again from the same point, but glide 10 knots slower and see where you end up. Yep, we all "know" what will happen, but when you (or, at least, I) actually see it happening, it concentrates the mind somewhat.