Ian Everett wrote:As I see it advantages of wireless over DCC are:
6) Any wireless loco can run on anyone's layout, be it DC or DCC, simultaneously with other types of loco
Only to the extent that the wireless doesn't collide with other wireless systems in use (try using wifi at a conference for IT professionals, if there has been no advance planning). Also, if your loco represents a short to the host layouts DC or DCC system, it will cause the circuits it is on to be shutdown for other locos. What affect that has on the layout will depend...
(and yes, even DC. DC systems aren't as fussy as DCC to brief shorts. But if you build your loco as a conductor from one rail to another, even DC systems won't like it).
It seems to me that people desire wireless for one main reason - to separate power supply from control. With wireless you have the clear option to deliver power via batteries or any other source that's not the rails. Delivering power to 2 rail track formations is sufficiently complex that a material number of modellers would really rather not.
With that said, there are a couple of challenges. Firstly, finding a wireless method that spans the range of model railways we build - from single turnout shunting planks, to multi-room systems. Whilst DCC might have a sweet spot for certain sorts of layouts, I think a big part of its appeal is that you can buy it in confidence you can use it on any sort of layout you might imagine. It's not yet clear to me that there are wireless protocols which cover this wide range.
The other challenge is all of the detail work around making the protocol robust - so a standard which several manufacturers can implement, a standard which means it's easy to have many layouts in one hall, and so on. It doesn't have to be a standards body - a defacto standard published by a successful manufacturer could also work.
It seems to be a good time to experiment with wireless, but for me both of those challenges are ones I want to see others solve before I jump in.