I found the maximum length and width confusing. It's all a matter of support. Technically you can just draw a line on a sheet and manually feed it WITHOUT any fence or guide. In this way the length or width is unlimited.
However for more accuracy a fence is required. As jobsworth noted when you are using the side extention/table, the LA stopper is very usefull. I started with the MFT3 table and also looked at the extension BUT with a separate CMS module the MFT3 can be use as an support or outfeed table.
Normally I cut down large plywood sheets with the guide rail while they are resting on both. This method can also be used if you want to take off a small long section (26 x2400 mm). I would use the parallel guide and some clamps.
The extensions are such that when you fold the CMS the extensions are not affected. No need to take them off. Which one to buy first depends on what you do. I ended up with the side extension AND the sliding table...
I made an outfeed table which can also store the modules. Works nicely
but adds to the footprint