When comparing mintty vs PuTTY, the Slant community recommends PuTTY for most people. In the question“What are the best terminal emulators for Windows?” PuTTY is ranked 8th while mintty is ranked 10th.
Ranked in these QuestionsQuestion Ranking
Pro Support for Cygwin and MSYS
Mintty is a native Windows wrapper around Cygwin but with added customization features like changing background color, font, transparency, etc.
Pro Xterm-compatible terminal emulation
Xterm is the standard terminal emulator for the X Window System.
Pro Proper support for scrolling in terminal applications
The mouse wheel in mintty actually scrolls the content in man/less/vim, etc.
Pro UTF-8 support
UTF-8 allows for the encoding of all possible characters.
Pro Drag and drop makes for ease of use
The drag and drop function in mintty allows the user to move an item quickly and easily.
Pro De facto standard client for SSH, Telnet and Rlogin
Pro Source code available
Full source available. Compile and modify it yourself.
Con No multiple tab support
Con No native support for WSL
Cygwin is dead. WSL is amazing, yet Mintty is designed around Cygwin and the WSLtty app to connect Mintty to WSL feels like a hack.
Con Win32 console API performs poorly
Classic Windows console applications don't work well.
Con Tedious logging/tracing
Its tedious to set up logging and tracing (e.g. for serial connections).
Con Lacks features
It is JUST an SSH client. There are many other options with built in X-servers, Multitabbing etc.
Con Can not save passwords
Anyway, you can use "PuTTYgen" to generate a key pair, then use "Pageant" to do a password-less SSH remote login.
Con No global settings
If you want to change a setting for all your connections, you'd have to do it individually.