CDG to Gare du Nord

You have heard the horror stories, so have I. The question is whether you as an experienced traveler will let yourself be concerned of these stories or lend them any credence. I would not. It's always in Paris or CDG where these so called horror stories pop up. I have landed at CDG from SFO at ca. the same time. The only difference that stood out against the usual CDG experience was one time I thought the luggage was rather tardy in being thrown out. I'm used to waiting 10, 20 or even 30 mins before the first bag is thrown out. Never noticed clearing Immigration at CDG (my last time was in May 2015) took excessively long.

The train ride to Gare du Nord takes about 40 minutes (assuming there is no delay in the system). With no checked luggage, in my experience that means most of the wait is gone. How long will passport control take? It could be 15 minutes or it could be an hour. Who knows? As a experienced traveler, you know that flights could be delayed resulting in a large number landing at the same time or people could call in sick etc. so it is hard to say how long immigration will take. Despite all the horror stories I have read about CDG, I have been fortunate enough to have never experienced a wait at passport control that was horrible, which to me is more than 20 minutes in the line and to put it in perspective, I have been through CDG 10 times since 2013. The worst waits that I have ever had have been in the pre-Global Entry days at Newark Liberty, JFK and SFO.

Clearing customs is a little iffy, but figure not long. 15 minutes with a little line. Less if you get there ahead of the pack.

Getting to the RER. It's a little walk and you have to go on their tram. Maybe ten to 15 minutes for the walk and another 15 on the tram. The exit from the tram seems a little strange, do they really want you to get off at a parking lot exit for RER? Yes, it's the correct stop.

You then need a ticket on the RER. There are machines and a ticket window. When I arrived there was no line at the ticket window but a few waiting for the machines. I decided to use the machines and couldn't get it to take my card, then the ticket window had a long line so I waited for the machines again and this time got it to work. A ten euro note would have come in handy but I hadn't stopped at an ATM yet.

I arrived on a weekday and the RERs ran regularly. I'm not sure if they have a lighter schedule on Sundays. It's a safe bet that it will take an hour plus before you are rolling away from the airport in the RER.

From there it's 40 minutes to Gare Nord, which beats a taxi or bus - they take about an hour to get downtown.

It depends on how many flights arrive around the same time as yours and how many people are on duty at the passport control.
Sometimes it seems like they are understaffed sometimes not. There is nothing you can do about it. I've been through there many times and don't remember being perturbed about it.

As the other posters mentioned, the wait for passport control is dependant on a variety of factors. I've never had to wait more and 1/2 an hour.

I am curious as to Brad's comment that one has to take a tram to the RER station. I've only taken trams from the arrival terminal to the Passport Control/Baggage Terminal. After clearing Passport Control and bypassing Baggage, I walk to the RER (also TGV) station. It's a nice walk after being stuffed in a plane for 8 hours.

When I was last there, the machines wouldn't take bills, but would take 10 euros worth of coins. There was a convenient bill changer machine. This is assuming that one has euros. I've had different cards work, and others rejected. No rhyme or reason. They all have chips.

When I was at CDG in 2015 buying a ticket for the RER, I went to the ticket counter, didn't want to wait for a machine, paid cash. The ticket was 10 Euro. Boarding was close by.

You don't pass through Customs at all, but Passport Control lines can be very long. Make sure you are in the right line for your country's passport.

Like most airports these days, CdG has an extensive website that will show you how to find the train station in Terminal 2.
http://www.parisaeroport.fr/en

Both the high-speed and regional trains are in the lower level and you want the RER. Separate ticket agents for the two services, too. I won't pretend CdG is fun; it's too big and complicated to be simple stroll. But it's a long way from horror story, if you do some preparations. The website has maps which can be printed out or maybe downloaded to an electronic smart gizmo.

From Terminal 1, there are signs in English to the railway connections. The ticket machines take most credit cards with a chip, although for some reason it wouldn't take the first Visa I tried. I tried another and it worked fine. Buy the RER ticket and just for good measure, get a carnet (10 tix) for the Metro and for buses. Everything is in English in the machines, and relatively glitch free.