I'm another for the 3000 rail. For the cost and transport issues, the 2700 is not enough smaller to matter. Neither is friendly for that, even the 1900 isn't so handy for transporting. If I had to use them for cuts that long in the field, I would probably go with a 1900 and a 1400. Cross cut full sheets with the 1900 and combine them for full length cuts. The 1900 is still pretty long, but manageable.
The exception to this, for me anyway, would be if you are using a router. I really don't like routing across the joint. I have had to, which is why I bought the 1900. I used a 1400 to crosscut ply and may never have bothered to get a 1900, until I needed to route a groove into a countertop to retrofit COVID screening partitions. Since getting it, I don't struggle with the 1400 on sheet goods.
Another consideration is the pistol-grip style clamp. I have one and use it a lot, but you cant use it with joined tracks, another win for long rails, but I am not mobile.