which museum pass to get?

The Museumkaart is absolutely worth it, but can be tricky to obtain for foreigners. If you purchase it at a museum, you will only be able to use it for up to five museums, as it needs to be exchanged to the plastic permanent card. The problem is, that you require a Dutch address to have it sent to. If you have some Dutch connections, you can have it sent to their home.

The card doesn't usually help with skipping the lines. Museums you definitely need to prebook are the Van Gogh and the Anne Frank House. I would also recommend booking the Rijksmuseum in advance. When you're in Haarlem, don't miss out on the Teylers Museum. It's great!

The IAmsterdam card is hit or miss and really depends on your plans.

To clear up the previous reply, the temporary museumkaart is worth it, if you add the total cost for the 5 museums you want to visit and it is less than the cost of the card.
The upgrade to the permanent (annual) card is no longer possible for the typical American tourist. Even if you have a Netherlands address to send it to, you must have a European bank account number to charge it to - they won't take credit cards. So for most tourists this will not be practical

We had the good fortune on our last visit to Amsterdam in walking up to the Van Gough Museum to purchase tickets and walking in, spending several hours there and enjoying lunch in their cafe. Mostly advanced tickets are necessary but sometimes you get lucky.

The Museumkaart is a terrific deal for those living in The Netherlands -- unlimited visits to museums (hundreds of them) for a year. For a visitor, as described above, it is difficult to get the full pass. We were lucky in that we had relatives in The Netherlands who could use the required debit card to purchase the passes. The cost for the pass is 64.90 euros for an adult (less for kids). Even at the limit of five museum visits for the temporary card that anyone can purchase at select museums, this might make sense. Just add up the entry fees to see. If you are visiting more than five museums, be sure to use the card only for the five most expensive.

For someone like me who will be doing Rick Steves 13 days itinerary as suggested in the book, is the IAmsterdam card worth it? I am thinking of getting it considering I will follow the exact plan like in the book.

I will not be using any car either.

My instincts tell me that the Iamsterdam card would be a good deal considering I will be following the book's exact plans (including the museums and canal boat ride + daytrips to Volendam/Merken.

We are back from our trip. Deciding about the museum pass or I Amsterdam was hard for me to figure out, reports that it was complicated to obtain the MuseumKart dissuaded me from it. What we did was, upon arriving at the train station at Schipol, went in and bought a multi-day tram/metro pass for the number of days we would be in Amsterdam. We loved having it and hopping on and off trams and the metro too. The entire transit system is so easy! However, the day we visited Haarlem, the train was totally messed up - they were repairing tracks - and everyone was routed to buses after one stop. It was difficult to find a person in Amsterdam who could explain what was going on, but at the train/bus stops, there were workers who helped direct the passengers.

The I Amsterdam card seemed pricey because some days we went to museums, and other days, we did not. So we paid as we went. and then we started getting choosey about which museums we really wanted to see.

Get tix for Rijksmuseum and Van Gogh ahead! Our hotel advised we didn't need to do so, and their advice worried me since it didn't jibe with what I read here and elsewhere; when I checked the tickets available a week before departure, there were no available slots for Van Gogh, but we did get tix for the Rijksmuseum. Have lunch there as well. Delicious and smartly organized so little waiting for table or food.

thanks to all who contributed advice!

Thanks for reporting back. Sounds like you had a great trip.
Your hotel was indeed wrong about not needing to buy tickets in advance for the Rijksmuseum and/or the Van Gogh museum. Even before COVID the Van Gogh museum had a time slot system to help control the visitor flow and now the Rijksmuseum has one too. You definitely need to book tickets in advance, especially for the Van Gogh museum which sells out days or weeks in advance. The same goes for the Anne Frank house btw. You must buy tickets for that museum well in advance!