[Bought together, otherwise I would have sold it to my husband :D
My sister is with Degussa and totally satisfied.
Honestly, what annoyed me a bit about ING is that they don't link the property financing with the house construction, but both have to run separately.
Honestly, I haven't had any other stress with them so far..
As I said, it always depends on what is important to you in financing... The interest rate alone is, in my opinion, not decisive – unless you are not planning to have children and plan a relatively stable standard of living.
With a bit of googling, I found out that Degussa only offers 9 months of interest-free provision period. The interest rate is said to be very high as well.
As far as I know, you can't flexibly adjust the repayment rate – I even think not at all?
Prepayment yes/no would also be a topic.
As I said... Not everything focuses on the interest rate – but ultimately it’s an individual decision. And I have to say that the price/performance ratio for US at the Ing-Diba fits more than just perfectly!]