I'll give you my view from the standpoint of having tried each of these HPs on the CK series.
I have the CK20HST, rated at 21HP. Most of the time I run out of traction before I run out of useful HP. In other words, my tires start to spin before the tractor will lug down causing me to have to stop and recover. On the CK25, there was a perceptible increase of power even though the frame is larger and heavier. Although it didn't have a loader on it, I did put it up against a tree and push to see how it would react. The same as my CK20, it turned the tires rather than lug on down.
Now the CK30 had a loader, and I took it out into my dealer's field to dig some dirt. It was awesome. I put the bucket down and dug as deeply as possible and even without a toothbar, like I use on my 20, it piled in the dirt and didn't complain.
The advantages you would get would really show if you were trying to pull something as in pulling out trees, hauling cut tree trunks, which my CK20 does very well, and pulling any kind of ploughing equipment. Now none of these three is going to be ideal for ploughing, but my CK20 will pull a one bottom plow and turn up dirt. The others will do that much better, will pull larger and larger tree trunks, and will do better at pulling out trees from the ground.
I'm now considering adding either a CK30 or a DK45 to my CK20 and keeping the CK20 for the smaller jobs and the other to pull larger implements for doing a small business. I first thought that the CK30 might not be enough tractor, but I'm beginning to change my thinking on it. I will be doing some more work with it soon to see just what all I can get it to do before I decide. The DK45 was outstanding when I tried it yesterday with a Woods loader. I pretty quickly adapted to the difference between HST and the shuttle shift of the 45, but I DO wish they offered it in HST as it's just less to do and I can keep my hands on the loader stick and steering wheel instead of shifting the F/R lever and pushing the clutch. John
I have the CK20HST, rated at 21HP. Most of the time I run out of traction before I run out of useful HP. In other words, my tires start to spin before the tractor will lug down causing me to have to stop and recover. On the CK25, there was a perceptible increase of power even though the frame is larger and heavier. Although it didn't have a loader on it, I did put it up against a tree and push to see how it would react. The same as my CK20, it turned the tires rather than lug on down.
Now the CK30 had a loader, and I took it out into my dealer's field to dig some dirt. It was awesome. I put the bucket down and dug as deeply as possible and even without a toothbar, like I use on my 20, it piled in the dirt and didn't complain.
The advantages you would get would really show if you were trying to pull something as in pulling out trees, hauling cut tree trunks, which my CK20 does very well, and pulling any kind of ploughing equipment. Now none of these three is going to be ideal for ploughing, but my CK20 will pull a one bottom plow and turn up dirt. The others will do that much better, will pull larger and larger tree trunks, and will do better at pulling out trees from the ground.
I'm now considering adding either a CK30 or a DK45 to my CK20 and keeping the CK20 for the smaller jobs and the other to pull larger implements for doing a small business. I first thought that the CK30 might not be enough tractor, but I'm beginning to change my thinking on it. I will be doing some more work with it soon to see just what all I can get it to do before I decide. The DK45 was outstanding when I tried it yesterday with a Woods loader. I pretty quickly adapted to the difference between HST and the shuttle shift of the 45, but I DO wish they offered it in HST as it's just less to do and I can keep my hands on the loader stick and steering wheel instead of shifting the F/R lever and pushing the clutch. John