Sorry if that came across as an endorsement. I'd go with the nordic modules instead because the documentation and support will be much better. The development costs of weird, cheap wireless chips isn't worth chasing marginal BOM optimizations. Just don't go to the other extreme and spend $40 on an Intel SoC for your wireless thermometer like I've seen others do.

I haven't worked with CSR modules since I left that job around 2017, but the latest vendor toolchains for some chips were still on GCC 3 (~2005) at that time. We were taking bare reels and doing certification ourselves if it matters though.