I already knew the twist/solution of TMOOE before I read it, but I had Death on the Nile spoiled as well and still managed to enjoy it much more than this one.
The resolution was pretty implausible but acceptable. What really bothered me was how static the rest of the plot was. The beginning was solid and intriguing, but it just felt like absolutely nothing actually happened after the murder. Poirot painstakingly interviews everyone and searches their compartments and that’s it. I realise that’s a necessary part of most mysteries, but take DotN as a comparison. There are similar interviews and searches, but they sometimes get off the boat and check out the scenery, there are things the characters do that Poirot notices, there are other murders. Things happen. In Orient Express, Poirot and Bouc just sit around and interrogate the passengers. I started to get really impatient with the middle third. Its static nature really impacted the atmosphere as well. You forget about the snow outside when the vast majority of the book is people sitting in the dining car talking about the alibis.
I find it a bit odd that people consider this one of AC’s best. It’s not horrible or anything, but I did find it kind of disappointing. It was just nowhere near as gripping as And Then There Were Now and Death on the Nile (the other two I’ve read recently). Might try Five Little Pigs next. I wanna read Roger Ackroyd, but I already know the twist so it’s hard to work up the enthusiasm.