There are several alternative brands and models that you can consider as an alternative to the DMG MORI DMF 180 linear machine, depending on your specific needs and budget. Here are a few suggestions:

1. Mazak Variaxis i-800: This 5-axis machining center offers high-speed, high-accuracy performance and has a large work envelope similar to the DMF 180. It also has a similar price point.
2. Haas UMC-750SS: This 5-axis machine from Haas is a cost-effective alternative to the DMF 180. It features a high-speed spindle and a large work envelope, and is known for its reliability and ease of use.
3. Okuma MU-5000V: This 5-axis vertical machining center offers excellent accuracy and speed, and is a popular choice for complex machining operations. It is more expensive than the Haas UMC-750SS but less expensive than the DMF 180.
4. Makino D500: This 5-axis machining center is known for its high accuracy and reliability. It features a large work envelope and a high-speed spindle, making it a great choice for a wide range of applications.

Ultimately, the best alternative to the DMF 180 will depend on your specific requirements, so I recommend doing some research and speaking with industry experts to find the right machine for your needs.