When it comes to automotive key programming and diagnostics, Xhorse is one of the most well-known and respected names in the industry.
Both the Key Tool Plus and vvdi 2 are powerful tools that offer a wide range of features and functions related to key programming, remote generation, and diagnostics.

However, there are some key differences between these two tools that may influence your choice between them.

1. Function:

Xhorse key tool plus 

• IMMO Programming
• Prog Function
• Transponder & Remote Function
• IMMO DATA TOOL (FILE MAKE KEY) Function Improved
• Control Xhorse Key Cutting Machine
• KEY TOOL PLUS - Maintenance Function.
• Cloud Diagnosis Mode-c

Xhorse vvdi2 full version

• Support Volkswagen Software
• Support BMW Software
• Support BMW Software
• Transponder Programmer Software
• For Toyota H Transponder
• New Function: add unlock CAS4 fast mode(5M48H/1N35H/1L15Y)

2. Differences

One of the main differences between the Key Tool Plus and VVDI2 is that the Key Tool Plus is an all-in-one programming tool that has a large touchscreen display.
This makes it easier to navigate the tool's many functions and features. It also supports more vehicle brands compared with VVDI 2, and offers advanced diagnostics and special functions.
The VVDI 2, on the other hand, is a specialized key programming and diagnostic tool. 
While it doesn't offer the same all-in-one programming capabilities as the Key Tool Plus, it is still a powerful tool for programming keys, generating remotes, and performing diagnostic tasks.

3.Pros and cons of the two devices:

Keytool Plus supports more brands than VVDI2, as VVDI2 is only capable of working with VAG, BMW, and Porsche. On the other hand, Keytool Plus can handle MB, Toyota 8A AKL, Ford 2016 onwards AKL, and many other brands. Keytool Plus has an added advantage of having a Key Tool Max, most of a Mini Prog built-in, and a key reader/programmer. However, to perform all tasks, one would need to purchase additional solder-free adapters, cables, and other accessories. Additionally, Keytool Plus can also control Xhorse key cutting machine, which VVDI2 cannot, as it is PC-based.

VVDI2 has the advantage of being PC based, making it slightly easier to navigate and input information. It is also more straightforward to save files for later use compared to Keytool Plus, although it is still possible to save files on Keytool Plus, it can be inconvenient to transfer them for use elsewhere or to share with someone else who is working on a car you have previously worked on.

Ultimately, the choice between the Key Tool Plus and VVDI 2 will depend on your specific needs and preferences. If you're looking for an all-in-one programming tool with a touchscreen display and comprehensive coverage of vehicle brands, then the Key Tool Plus may be the better choice for you. On the other hand, if you're looking for a specialized key programming and diagnostic tool, then the VVDI 2 may be a better fit.