For the most part, no. Exception would be when a beta release includes a feature/fix that I need. I don't do betas for OS or any low-level programs (security software, drivers, backup, etc). I need stability, predictability and long-term support for these. Sometimes, I post suggestions when I see active software development where the developer participates and ask for feedback. I don't do bug reports though. It's just not my thing.
I quite frequently beta test but only ever on *my* systems. There are some exceptions where I've tried beta testing something and it's been unstable several times, at which point I never bother beta testing that software again. An example of this would be Chrome which is too frequently unstable.
I like to beta test and especially closed betas , the number of testers is reduced and the interactions with devs are deeper; when a product enter public betas i generally stop or focus less on it letting the public testers take over the product.
Lost patience with my Chromebook not receiving the latest stable, switching to beta channel (which has MTP support!). Might as well do the same for my other machines.
I used to beta test Firefox prior to their 6 weeks cycle of updates. Had enough of it and don't want to participate anymore in anything beta.
I do but I am v e r y careful. Last one was ESET NOD Antivirus 8. I am also using Windows 10 but that's not even in beta yet. For the record, I really like it.
It's the same for me. I'm always prepared to try out a new version of a program even if there may be issues which need to be resolved.