I very much enjoy performing lunges. Personally I feel they are much better than squats and very functional. In some variation they are performed every day even more than squats. Lunges, if performed properly, place much less stress on the spine. Whenever one performs a squat the lower lumbar spine, sacrum & coccyx must retract a bit. For folks with lumbar spine issues such as herniations, ruptures, etc. this can be very uncomforable and place a load of stress on the spine itself. The lunge tends to keep the spine more neutral and allow it to remain straight as long as form is sound.
One of the best workouts I enjoy taking myself as well as my clients through is the Quarter Mile Lunge Fest. We lunge a quarter mile without stopping and then have a mini Belly Blast session right after. Of course I make sure my clients can hang before having them attempt the Lunge Fest, but overall it feels great and the legs & core grow much stronger when performing lunges. Throw in a 10 min. Kettlebell Jerk or Long Cycle set after one of these great lunge workouts and call it a day. You will get in amazing shape.
Give it a shot and remember Fitness Has Nothing To Do With Looking Good!