I was recently researching this as well. From everything I have read it seems like the Handy is superior the Keon/Launch as it doesn’t have stuttering and has a higher rate of speed. Seems like the biggest issues that people have had (solved already) is mounting them for hands free play or modifying them for alternate sleeves.
I have not looked much into any other toy, but you might also want to look into the OSR as from what I have read it seems leading edge. I still need to do more research myself:
https://yourhobbiescustomized.com/products/osr2-by-tempestmax
Link to some useful information on the handy below:
https://discuss.eroscripts.com/t/handy-sleeve-alternatives/831?u=muddycakes