I have been doen this road before when a local hero / grade three instructor protested loudly my use of side slip in a 182. have thought about it and experimented with it at altitude and came up with -
* Cessna flaps are not designed for a sideways load (have a look at them next time you pre flight a cessna and you will understand)
* The 'side on" relative airflow to the pitot tube will cause you asi to under read ( C-182 80 kts indicated at 30 degrees side slip equals 100 kts, try a side slip while watching the asi for confirmation)
*horizontal stabilizer and fuse shields part of the elevators in the side slip reducing control authority (experiment with this at altitude very gently as it will be apparent even at small angles of bank)
* aiming point can be off to one side in a side slip and can be used to correct position as well as height.
Finally don't listen to any crap about side slips being a thing of the past or only good for fixing a bad approach, learn them at a safe height and then chalk it up as a tool of the trade.