Launch X431 PRO MINI WIFI Bluetooth is newly released to replace X431 Diagun III, since Diagun III stop production. Being a replacement, X431 PRO MINI must be better than Diagun III in many aspects incl. hardware specification, special functions, etc..
Read this comparison table between Launch X431 PRO MINI and X431 Diagun III
In conclusion:
Launch X431 PRO MINI WIFI Bluetooth wins
in special functions
In screen size
In Operation system
In Update online (2 year update for free)
In price