I loved mine when I had it, although it seems a bit redundant if you've got the Sigma 30mm? I found it was very particular about the infinity stop. Worked great with one adapter and not with another. That may be your issue. Lovely color, handling, and of course size!
There will always be some FL overlap and redundancy when trying lenses. Too hard to pass up some. I wanted to try out the Takumars. And found them worth building a collection. The modern glass usually outperforms the vintage, but the Sigmas have a colder look compared to the old coatings. Some of them have such nice character and render very appealing results. For example, the SEL5018 was one of my first additions. I didn't need another 50 given its performance. But I have a dozen 50s now. Some are keepers, and I still have more coming in to try.
Discovering those that make you say Wow!, is fun.
Also ran into a situation where the modern lenses failed me. They struggle to focus in low to no ambient light shooting. But I took my native lenses assuming I'll assure myself of success. A prepared manual focus lens was the solution.
I have another M42 adapter I got for long teles, will throw it on that and try again. The Taks are great, even after 40 years.