Tractorkid: I just wrote up a deal parting with my old
B7100 for a newer larger machine. I looked long and hard. The JDs are sold by a former student, but price did them in for me. The Case DX26 looked like the winner after a long search, aided by availability of A-Plan pricing. Then I sat on a DX29. It looks huge compared to the 26 in person, but use a tape measure or read the stats. It's actually shorter overall despite having a 5 1/2 inch longer wheelbase. There is no contest regarding hydraulics, loader, etc. The ergonomics are great.
I don't know what you are looking for exactly. I thought the 26 would be great step up from my little 'bota, but the 29 was not much more in price and a whole lot more tractor. Drive one and see what I mean.
BTW, I got 4500 in trade for my 7100 gear with loader, and this is with A-plan on the Case. A Mahindra dealer only offered me 3000. What you can get for your Kubota may make up your mind for you.
Green or red, either one is a good machine. The red one has been around a little longer, the 2520 is a new model. I don't know if tractor lines have "bugs" in them when they first hit the market or not, but it's something to consider. Look at service requirements and costs and warranty coverage. You should be able to get 0% financing, but look at the bottom line if you go that route. Have them write up a total price deal including trade, financing origination charges, set-up, delivery, manuals, everything. Then compare. And if red wins out over green, go see the guy who sells the blue version and get his price for the same machine the Case dealer sells. Blue paint might be cheaper.