It may be best to note that the VF-25F/S kit manual uses "design" and not "ultimate" to describe it's load limit. By design, its load limit is that amount indicated. But it's not necessarily the ultimate limit where it would snap into many many pieces (of which you'll probably have to factor in speed, weight, etc of the time it broke into many pieces).
This is also a good time to remind us that newer products don't have to be faster or carry more weapons, etc. than their predecessors. The VF-25 and VF-27 incorporate EX-Gear (the latter still up for debate) and ISCs to compensate for stress on the pilot. Having EX-Gear also gives the pilot a better ejection system than the previous sitting-duck-escape pods. The VF-25 and VF-27 still perform about the same within atmosphere compared to their predecessors.