As a new member of the O Gauge realm, and an old school guy, I have focused on buying the all metal, heavy, Lionel cars from the 50s and 60s. Why? Because they stay on the tracks, sound like real rail cars when going over track joints, and give me no problems whatsoever. The big lobster claw mounts work, and are easy to deal with.
Here is the problem with the new Lionel cars: The smaller square-interior couplers they are using will not hook up with the older reliable lobster claws. The interior of the couplers are too small to lock onto the larger knuckle of the older cars, and often they are a tad lower than the older couplers, and if by some miracle you can get them to lock together, then because there is zero "play" on the inside of the joined couplers, the newer cars derail when the train passes through tight turns at medium high speeds or through crossings and switches.
So, in short, Lionel is now making cars with cheap couplers, that will not couple with the superior classic cars of the past, and they seem to want us to ignore that little problem and pay big money for the new cars.
Sorry, not me. Gunrunner raised a valid point when he said, If you don't buy from Lionel, who are you going to buy from?
Answer: People like me will do the same thing that tens of thousands of people did when Remington cheapened up their products to the point of no return: Buy the older used products from 30 years ago, for bargain prices, and fix them up. (Because the older products were built to be fixable, they can be easily repaired.)
I have been a loyal Lionel fan since I got my first train set in 1964. My transformer, tracks, switches, and every railcar except one, are all Lionel. But, I cannot buy new products with problems. Life is too short.
I hope Lionel will fix this issue, and I would gladly pay $5.00 or so extra per car, to get one that works.