I had my bachelor degree on TU Graz in mechanical engineering and I was living there for 4 years.
Overall, Graz is a really nice place to live in and TU Graz is a great University to study at. It has the best mechanical engineering course in Austria and has a big industry in the city to support that. University is, in my opinion, perfectly organised. Everything runs smoothly and what does not is quickly being solved. Classes are good and are supported with a lot of practical workshops. There are many student projects you can participate in and societies you can be a part of. Both are getting great support from the University. There are sufficient amount of student jobs you can do on TU Graz, albeit these are limited and you will have to be above average student to get them.
City itself is small enough to be practical to live in and big enough to be very alive. There are many students separated in 4 different Unis so you can meet a lot of different people. It is a bit expensive to live in.
You will surely enjoy living and studying there, I can only recommend it! Thank you for reading and I hope it was helpful!