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Don't be afraid to play higher Bots!

Wow absolutely fantastic post! I couldn't agree more. My recent blog post discusses this very thing and my extensive training plans involve bot play as a large part of my strategy to improve my play. You refuted quite well the many false claims that keep being spouted hating on bots and the source of the claims were well said. Also I had NO IDEA that the bots get stronger the better the computer you are using! That is crazy! VERY good to know that.
I noticed that many users discredit bots: "they don't play like humans", "it's easy to beat 3200 elo engine", etc blah blah.
Then I investigated a bit and discovered that many of these users play Bots on small, mobile devices! Nelson on iPad is hardly over 600 Elo. These devices have weak CPUs.
Here's an example of On-the-Board tournament player who had to work hard to beat Antonio (1500). It took him 58 moves. And his FIDE rating is over 1850.
I played Antonio. Bad idea.
He's got a strong desktop machine built for chess engines, so the bots perform on real levels. And Antonio is the weakest - if you have basic understanding of positional play, you can't loose from him.
So the reasons for bot trashing are mainly psychological: when you play higher bots on strong computer, you face your own incompetence and ignorance. 2000 online blitz players who never studied chess theory, usually struggle with Antonio, while +2000 bots literally wipe the floor with them (even in slow games).
But I understand that online Blitz is played for FUN... This time, though, is wasted time, because you learn much more from two 60min games per week played against strong bots. Even if you loose. Particularly if you loose! Bots never give up, they never resign. Some say "they make inexplicable blunders" - well take a look at tournament PGNs, even FIDE masters make inexplicable blunders when they're exhausted.
These stronger bots are so good they're used by OTB players for tournament preparation. Human players cannot "torture" you like the Bots do
Anyway, congratulations to chess.com for making this possible. I would also suggest making dedicated training software with these bots, which can be used independently from browser and Internet. I believe OTB players would pay for such software, as a nice complement to Chessbase, for example.
Good luck!