Ask HN: Are there are any good alternatives for MS Project?

I have used MS Project in the past on my job and love its functionality.

Now I need project management tools to use in my own company and I find MS Project to be quite expensive considering that I want both my test/req lead and programming to be able to break down their assignments into sub-projects and give visibility to the rest of the team.

Are there any stable and cheaper alternatives to MS Project?

I have tried Open Project, found it has quite a lot of bugs and wouldn't want them (or myself) to waste time trying to overcome those bugs.

I have also tried an online service 6 months ago (it mostly did gantt charts), it was horrendously slow and impractical for that reason.