Got my set delivered today for my L2501. Kubota couldn't make a higher quality or a better fitting set of floor mats. The entire process was a pleasure, quick and hassle free. Thanks!
I have the Bora 3.5" on my L2501 along with filled rear tires. I think it's much more stable. Like you, I questioned the size to get and called the company. They were very helpful and suggested at least 3" as I recall.