When I returned to the hobby, I initially went with N for a number of reasons, one being the seeming incompatibility of couplers across the HO manufacturers: N manufacturers all seemed to be using the same type, so whether the item was Arnold, Minitrix, Fleischmann, etc., everything worked well together.

There also wasn't the two-versus-three rail/middle contact decision to make either ;) If I were to re-enter the N scale arena once more, I would definitely consider the Kato Unitrack system for its simplicity, even though it's a little pricey.

A bit more on DCC... the standard to date has been 6 pin plug in but recently, at least in Euro models this has diversified into Next18, minitrix proprietary 14 pin, plux12 and plux22. Just something to beware of if going the DCC route. Also not all models are DCC ready with a decoder socket. Some still need soldering in

(I never expected my knowledge of N to come in handy on this forum!)

C. :)

Well if you are considering other options.....how about Z scale?

Carim

Actually no worries if you install telescoping axles on the trains!

I switched to N from Marklin HO a little over 10 years ago now and haven’t looked back (although my future dream layout is still a Marklin HO railroad). These days you will find most new locomotive releases have a sound option available for the factory. It is only older models where you will be somewhat limited - and finding room for sound decoders will be mostly impossible in many loks that are not ready for sound. That said sound in N is not all that great as an 8 or 9 mm speaker cannot put out that quality of sound that a HO scale speaker can. Manufacturers often ship the locos with the volume set way too loud for the tiny speakers and that does not help either. I try to buy as many loks now with dcc installed as the growing number of decoder socket standards is getting to be a pain. With the old NEM 651 6-pin decoder it was not an issue but these days it seems you have to buy a manufacturer’s specific decoder for each loco.

I use Kato Unitrack for all my hidden staging areas as I have found it needs less maintenance than any other track brand (the metal just resists oxidation better I guess) and I use Peco code 55 track and turnouts for my visible areas as it looks much closer to scale. The code 55 track has some Rail embedded in the ties so it looks fine scale but also allows for the deeper wheel flanges of euro n scale. When I first started in n I tried using unitrack for everything but I just didn’t like the look of it in the visible areas. It is great for planning and getting an idea of what I s possible before laying track permentantly (just like c-track is).

The Arnold rapido coupler is still the standard and it works pretty well however the Flesichmann profi coupler is quite nice and has a few advantages. Most newer loks and rolling stock will have NEM coupler pockets so exchanging couplers is easy.

Other have listed the main manufacturers and Trix/flesichmann still have the highest volume of new releases followed by Arnold. New molding seems to have slowed down in recent years due to tighter budgets but other brands such as Lemke Hobbytrain and Modellbahn Union have picked up the slack by producing new models of ‘missing’ loks and rolling stock. Much like Marklin if you see something you like you generally have to order it when it is announced or released to retail as many models only get a single production run. Although eBay Germany is a always a good source for deals and out of production models - just be wary of used locos as many can have more issues than initially evident and parts can be a pain to obtain.

Lots of questions marks. Are you asking questions? Or are you unsure about your statements?

Some Z gauge locos in the Märklin catalogue are actually AZL products in boxes with Märklin logo ("co-operation"). So it is not all by Märklin.

I assume that contact problems increase when size reduction increases: N is worse than H0, Z is worse than N, ZZ is worse than Z, T is worse than ZZ.
It's similar for choice of models.

Some are happy driving a perfectly detailed I gauge loco left and right on a straight track, some are happy with a Z gauge layout that allows running long trains in a small space.
Make your choice - or maybe have both: a I gauge loco for the shelf, and a layout in Z or N or T.