What's the best DS-2CD2432F-IW firmware?

[Mr.Mike]

Hello,

My DS-2CD2432F-IW bought from Wrightwood came with:
Firmware Version V5.1.0 build 131202
Encoding Version V5.0 build 131128

It's Serial No. DS-2CD2432F-IW20140901CCCH478xxxxxx

The sticker on the back says:
09/2014
V5.2.0_140721

I'm guessing it's a Chinese cam but the GUI is English, which I want.

What firmware would be best? Where to get the files?

Thank-you, Michael F.