Excellent product.

In a previous company I worked for, there was a policy where we only used OKI.

Update 2024: It tends to destroy the drums.

Purchased in June 2018 for use in a small office with moderate professional printing and more intense scanning use. In January 2021, when the second machine (HP) of the office gave up, we decided to get the same one.
Advantages
1) Small volume for a professional machine. Its size is acceptable even for home use.
2) Low printing cost. Original toner has never been used, but quality OEM toner has been used without any problems.
3) Quality printing and truly automatic double-sided scanning. I mention this because many manufacturers claim automatic double-sided scanning (e.g. HP m277dw), but in reality, it is an improved version of manual scanning that requires some user involvement.
4) Extremely reliable so far. Of course, time will tell, but overall the machine shows sturdy construction.
5) Wi-Fi connectivity and 3-year warranty.
Disadvantages
1) It has been on the market since 2015, so it is older technology. However, this can also be seen as a positive, as it continues to sell, indicating positive evaluation by the market.
2) Its menu is not exactly user-friendly (like most OKI printers), possibly because the machine is not primarily intended for home consumers. It's not a big issue, it just requires some time to get used to and to read the manual carefully before installation. For example, to install the network, you need to enter an administrator password (the default for OKI is aaaaaa). If you don't know this, you'll have to search for it.
3) The only real drawback it has is the wireless scanning through the OKI Act Key application installed on the computer. It is very slow and frequently disconnects. My supplier told me that the problem can be solved by scanning directly from the machine instead of using the Act Key application. I have no reason to doubt him as he is a reliable professional, but I didn't bother to try it as I solved the problem by connecting it to the computer with a cable. However, if someone is interested in wireless scanning on computers that are far from the machine, they should check this before purchasing.
Conclusion
It is an ideal value-for-money purchase (even if the price reaches €300-350) for small professional offices with intense use or for medium-sized offices with moderate use that should consider this option before going for larger and more expensive models. It is also suitable for home use, where it is estimated to last for many years.

War dog. Seven months working in a small office. Purchased as a backup printer - mainly for photocopies/faxes we wanted it for - we ended up sending our printouts to it.

The best purchase I have made.... Fast and economical...... at €180 that I found it was super value for money... I highly recommend it without hesitation....