You'll get a lot of responses that subframe is better, and generally speaking, I think it is. However, keep in mind that the factory Kubota hoe (the only one that will provide any reasonable assurance of warranty coverage) is a 3 point mounted hoe. After considering that, it seems unlikely that the 3 point hoe is the certain death spiral for your tractor that many seem to think it is. If it was, it would seem Kubota wouldn't sell it configured that way.