At home I disable mfx in the controller - for comfort's sake.
At club meetings mfx sometimes has advantages. But with the CS3 it seems very buggy and sometimes we waste a lot of time trying to get Märklin locos to register.

Yep. This reduces the usefulness of the outcome of this poll to some extent.

I have a CS3+ with two simple layouts at home and our club has a CS3+ with a very complicated layout. Neither one has had issues registering mfx locomotives. Occasional problems with both on older locomotives. The one concern I have heard of though not observed is that if you take a mfx locomotive registered on one controller and then register it on another controller you supposedly have to register it again. Also the club controller has so many locomotives registered on it that I think it is beginning to repeat addresses and this seems to be causing locomotives to repeatedly register. Though I am not certain that is what is causing it. Need to do a listing of addresses to see.

Hello, good morning,
I, whenever I can I use DCC, but I have many locomotives with decoders that only understand MM, that is, delta decoders, 6080, 6090, 6090x, etc, therefore I use DCC and MM, this option is not present in the survey, which I think is wrongly posed.
Greetings to all

Mostley of the model railway change out old decoder to better.
A lot of people choice a protocol after changed out decoder to newer.
My poll vote question are clear about what protocol do you use with digital locomotives.
In this case you can only use one protocol to control your locomotive in digital.

Dear Goofy, I'm not sure I understand you correctly.

Just because there are a majority of hobbyists who swap out old decoders for new ones, doesn't imply that everyone does or should do that. In my case, there have been times when I have bought a delta locomotive and I have indeed changed the motor and decoder to a higher level, but it is an isolated event, fortunately I have enough locomotives and I can not consider upgrading them all to the latest level of decoders, besides that "The latest is not always the best".

[A lot of people choice a protocol after changed out decoder to newer.]

Yes, of course, the example of the delta locomotive with MM decoder and that when upgrading it to a 5* engine and Lokpilot decoder, I manage it in DCC, my control panel an IntelliBox of 1st generation, is multiprotocol and I can manage a MM locomotive and another DCC, simultaneously, there is no problem.

[My poll vote question are clear about what protocol do you use with digital locomotives.]

The question of your survey is clear, but the possible answers are not, because you should have enabled the option to choose several answers, I, as I have already told you, I can handle and manage, simultaneously, in several protocols, which are DCC and MM, and I preferably choose DCC and when the decoder does not have that possibility MM. This answer DCC and MM is not in your survey or poll and I am sure it is the case for many marklin-users.

[In this case you can only use one protocol to control your locomotive in digital.]

Yes, you only use one protocol to drive a locomotive, but in my layout, I drive several locomotives, each one with its own protocol, simultaneously, in my layout are running, let's say, 11 trains, and some go in DCC and others in MM, simultaneously, each one receives its orders in the protocol that corresponds to it.

Best regards

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Märklin is one of the speech that tells to customer use only one protocol to avoid digital interference by use too many protocols on the same track.
That´s way to changed value before start use trains.
I see lot of videos in the Youtube how big difference it shows and works with severals locomotive decoders in function that are better than Märklins.

Märklin recommend disabling unused protocol.
AFAIK they do not recommend replacing old decoders.
AFAIK they do not recommend using a single protocol only.

I prefer MFX, but if I need funtionality that is not supported by the MFX protocol, I disable the MFX and MM protocol on the decoder. Usualy this is due to the need for controlling an entire train by consist address or the need to control a separate SUSI decoder that requires DCC commands. The consist address is usually needed to control interior lighting and automatic switchover of the red marker lights on the first and last wagon since they follow the direction of the locomotive.