We will probably see how it works.
The canal trip is 8 to ten hours, a very short time. They are apparently designing or building a new third canal that is much wider as only 40% of commercial shipping can now make it through the locks. The new canal will be able to handle much larger ships and put them through at about the same number of hours.
The rail facility spoken of is apparently an attempt to handle the ships that do not fit through the canal but it appears that the new canal may make the rail facility moot.
The current charge for a container ship is 72.00 per standard container, very, very cheap in transportation terms. It is going to be very tough to beat.
These things leverage productivity so well that virtually everyone was totally startled when the Chinese began laying down products next to their own factories at half the price, or less.
The global economy has not yet recovered from that shock. It's like the Pacific Ocean wasn't there anymore.
The Chinese see these Panamian and Columbian projects as something that will make Europe and the Middle East as accessible to them as America ~ and at a real long term cost less than that of going through the Sunda Straits, or around India (a potential enemy state), or through Suez.