May be I should apologies for my definition of a 'toy'. I am not professional and I am not paid for playing...
It is just so that after real piano I was unable to find some satisfaction in the digital world in the affordable for me price range. Several years ago I have systematically tested everything with keys, from $300 up to $3000 (thanks to the shop in the near, which always has them ALL), days long, reading reviews, technologies and discussions. I was concentrated on Digital Pianos, but with often travels in mind, I was also testing small format synth actions.
My conclusion was that middle range hammer actions are acceptable for me (decision between Yamaha and Kawai was hard). For lightweight solution I have noticed MIDI keyboards not only smaller then something with sound module (like PSR) but also of better quality for the same money. I was surprised that I prefer light synth action over semi-weighted and I have no problems with Roland's short (in length) keys.
About sounds. From technologies, discussions, playing with Sonar and testing real devices, I come to the conclusion that computer synth sound generation is way better then "hardware" way on cheap devices. The fact is that producers are using quite old hardware for all models.
All that is subjective, not professional, etc.