Well, speed-cubing is an interesting thing.
If you'd like to try it out, you're probably good with a <$10 cube as long as it's not "Rubik's" (They're ****).
If you'll get good at it then there's enough cubes to choose from - just like mechanical switches, each has different "feel" to it. There's even the lubing aspect that we share with our hobby. What's plastic without lube huh?
On the plus side - even the most expensive "top-end" cubes cost like $60-70 so compare to keyboards it's a "cheap" hobby to get into.