The latest collector-oriented, wide-distribution lines from Hasbro are an outstanding value, with interesting transformations, durable enough for kids, and pay homage to the characters their parents know from the '80s. I'm talking specifically about Siege, Earthrise, Kingdom, Legacy, and Studio Series 86.

https://tfsource.com/hasbro/transformers-studio-series-86/

https://tfsource.com/transformers/war-for-cybertron-trilogy/...

https://tfsource.com/generations-legacy/

Cyclonus in particular is an amazing toy for kids or adults: https://tfsource.com/tfsource/cyclonus-and-nightstick-voyage...

You can find these at Target or Walmart in the US for even cheaper.