Building savings loan - Good alternative or pointless?

Hello everyone,
we have an offer from a bank for a loan amounting to €200,000.
€100,000 through a building society loan and €50,000 KFW124 and €50,000 annuity loan from the bank itself. The two loans from KfW and the bank are self-explanatory. What concerns me is the part from the building society. I have read a lot about this and actually it was almost always advised against. Unfortunately, in our specific case, I cannot identify any of the negative points. Maybe you can explain the problem to me. Here are the details:

Pre-financing loan ZB until allocation 1.85% (rate €150 interest)
after allocation through the building society 2.60% (rate €250 savings contribution). Overall 2.43% for both combined.
each effective interest rates. Overall, this building society model is about €10,000 cheaper than an alternative offer. Where is the catch?

Furthermore, we have another alternative offer from R+V. The loan is called Fix & Flex. Basically, we like this model better. Just more expensive. Does anyone have experience with this loan?

Yes, at the time I also had some headaches with the integration of a [Bauspardarlehen].

Disadvantages:
- Fees 1% of the [Bausparsumme]
- No 100% guaranteed allocation after 10 years, depending on the financial situation development of the [Bausparkasse] (theoretically, it could also become allocable later)
- Usually higher savings rate required during the saving phase, meaning a larger portion of the repayment goes into the [Bauspardarlehen] and less into the annuity loan
- Contributions during the saving phase do not reduce the interest burden

Advantage:
- Interest rate secured in 10 years
- Usually more favorable interest rates possible than with an annuity loan
- Flexible in repayment and contributions, possible to refinance after 10 years with an annuity loan if interest rates are then lower

In short, we also realized a tail on that to hedge the risk. You can often negotiate a little on the interest rates for the bullet loan.

Super. Thanks for the quick response. Regarding the disadvantages: - The savings rate (and overall the monthly burden) is lower than with the alternative offer; - It is true that the interest rates during the saving phase are very high, but in the end, it means €10,000 less. - And that the allocation is not guaranteed is correct, but the interest rate of 1.85% is secured until the allocation. If the allocation, for example, takes place 10 years later, that shouldn't really matter to me, right?

My gut feeling is still against the building society, but most of the disadvantages are not disadvantages for me. From this perspective, there are actually quite a few points in its favor.

With us, a 10-year bullet loan is agreed upon until allocation. That means if the allocation takes place only after 11 years, we would have to bridge the financing for 1 year.

So far, the building societies have been quite reliable with the allocation. To what extent this will still apply in the future is the question.

I also have a combination of a [Tilgungsaussetzungsdarlehen] / [Bausparvertrag] from Schwäbisch Hall over a total of 25 years with a constant rate. It has also been significantly cheaper than all comparable 25-year full repayment annuity loans.

Hahaha... that was good Jay69. Taking all costs and opportunity costs into account, I guarantee you until proven otherwise: definitely not.