Any kind of weight bearing method, preferably internals and not LON. Since femurs heal faster and you will have weight bearing nails inside your bones, you will start walking much sooner compared with PRECICE 2 nails.
PRECICE 2 has many problems due to not being weight bearing. It bends or breaks, thus requiring another surgery for replacing nails that will cost huge amount of money. Being wheelchair bound for months is not a joke and I think it just doesn't worth it going with PRECICE 2.
It's kinda pathetic that LON patients can walk during the distraction phase but PRECICE 2 patients can't. Until bone bridge appears, it's not recommended to walk with PRECICE 2 nails and that won't happen for at least 4-5 months post surgery.
IMO, for 5 cm, going with LATN tibia is much better. You can walk during the lengthening phase and after you stop distracting, they will insert much more stable nails compared with LON. You will be able to walk with crutches and after sufficient bone bridge, you can walk unassisted and wait till bones heal completely.