Is the full-sized layout going to be N-scale? If so, I don't even know why you would be considering RailPro unless you are planning on putting the receiver in a box car and rigging some sort of custom wiring harness to the locomotive.
As I mentioned, for the N-Trak layout, I would be purchasing a Digitrax DT4D. At this point my home layout will be HO, and that's where I would use the Z21 (or RailPro or whatever system I settle on).
What function numbers are you having to remember? All the systems I use have a button that says Horn, Headlight, Bell, etc. I really seldom think Oh yes Headlight is sending F0 to the loco. The only remembering I ever have to do is when I am running someone else's locomotive who has gone in and customized a bunch of stuff. In running DCC for over 20 years now, I can only think of a couple times I had to remember something like, "on this particular brand of loco that F9 F9 was the reset and restart of the sound". Oh yeah, and once I looked up which functions I needed to select to do the Doppler effect for a video we were making. These are not the sort of thing that is going to be programmed into the Roco system by default.
Upon closer inspection of the DT402, I do see the symbols for bell, lights, coupler and I'm assuming the 2-button is the horn (can't tell for sure what that symbol is from the photos). Do you have to program those functions, or is that covered by the NMRA DCC standard? Also, when selecting a loco to control, I would much rather select it by name or, better yet, by its image.
The Roco is one DCC system that I have never used. For the tablet control I like the view that it has where one is looking at the actual control panel of the locomotive and is viewing out of the cab window; however from their information I was unable to determine if that option is available for any North American locomotives diesel, electric, or steam; or in N-scale. Are you planning on running European equipment?
Nope, and while that seems like a neat feature, it's not one that interests me most about the product. Personally I would prefer the default control scheme to the cab view, which appears to require two-touch operations for everything (touch the control to bring up the lever, then touch again to operate the lever).
I don't understand this statement, nor can I find anything about it on the Roco web site. But DigiTrax throttle run on a proprietary throttle bus called loconet. Unless Roco has paid licensing fees their throttles cannot work with Digitraxx command units and vice versa.
As fcwilt pointed out, the Z21 supports LocoNet. You can plug DigiTrax throttles directly into it. I believe the DigiTrax throttles can also be connected wirelessly as well, but I need to do further research to confirm that.
As for using a smart phone for a throttle, I don't understand the desire to do such a thing. If not the "in cab" experience of above, then I want to be watching my train run not looking at an electronic screen. So for that part I have no comment, other than I noticed if you buy this unit they recommend also buying the "Multi Central Pro DCC system with Rocomotion program". I am guessing that is where you have to program all the DCC functions to screen buttons stuff that you don't want to have to remember.
Smartphone, DT402D, either way you either look at the throttle to operate it, or you get familiar enough to do it without looking. I don't actually see myself using the camera feature, as like you said, there aren't many (if any) North American locos that implement it. Still, a view from the cab of your train, as it rolls around your layout would be pretty cool...sometimes. It wouldn't have to be an either/or thing.
If price is a consideration, and if I am reading the prices right, and doing the euro calculation right, that is a MSLP or about $847 for the system assuming use of a smart phone.
I don't think that's correct - at least not for someone in my shoes. Mine would be a fairly simple layout, likely for quite some time. Later, as the layout grows and becomes more complex, I expect I would be investing more in the system. Of course that's pretty much the case with any of them, right?
I was going to recommend you look at the Zimo system, but it seems they are in some sort of system upgrade mode right now. Neither their old nor the new products are available at the moment. Wonder whats up with that?!? Then the
Bachmann Dynamis Ultra looks like it has a similar interface to the Roco but in mono-tone color. Would probably be much cheaper than the Roco. Once again the caveat here is that (like the Roco) I've never even seen a Bachmann Dynamis Ultra, let alone experienced one, so I don't know how much this input is worth.
I've not heard of Zimo. Though if what you say is correct, it's probably a non-starter for me. [EDIT: HOLY CRAP! $2-grand for the basic Zimo starter set - and that's without wireless!] I've seen very little regarding the Bachmann Dynamis Ultra, but what I have seen has been as much negative as positive.
I realize that I'm "the new guy" with this stuff, and I didn't mean to rub anyone the wrong way or buck the system with my impressions of current mainstream DCC systems. I do also realize that my opinions at this point are based on very little, compared to the experiences of those who have been in it for decades. I can appreciate that people who have used DigiTrax for such a long time can program and operate it in their sleep. Coming in with a fresh perspective, however, it just strikes me as an interface that has not kept pace with what not only is possible, but expected in this day and age. I guess it just boils down simply to the fact that it just may not be the right choice for me, when other systems may come closer to meeting my own interests and expectations.
@fcwilt - If I may ask, have you seen the effectiveness of speed matching and consisting with the RailPro system? Does the Z21 system come close to that, or, being DCC, is it pretty much the same as any other DCC system? I found the load sharing feature in RailPro more than a little impressive.
https://youtu.be/xk0WLpqwfO0?t=406
