I tried one of these 120a TSKY ESC last week. Bear in mind I have the hobbywing 3 in 1 program box and I don't think the sky USB link will work. Here's the update procedure that worked for mine (from memory):
1) Download the hobbywing software to the PC, install, restart PC.
2) Unpack your 3 in 1 program box, use the included USB cable to connect it to your PC.
3) Start the Hobbywing programming software. Switch it to LCD Program Box mode:
4) Click 'Firmware Upgrade' on the left and then in the main window follow the prompts to update your 3 in 1 hobbywing program box to the latest firmware.
5) Let it complete, unplug the hobbywing usb, close the software.
6) Connect the receiver wire of the TSKY 120a ESC to the hobbywing program box (correct port, the middle one), and connect a fairly charged LiPo to the ESC.
7) Plug the Hobbywing program box back in to the computer.
8) Start / restart the hobbywing software.
9) (Make sure the Device menu has 'ESC Program Mode' selected).
10) Click 'Firmware Upgrade' again, the latest firmware should be chosen for you but just make sure (mine was a V3 I think), then hit update and wait until it's all done.
11) Once the update is complete you can optionally close the software and reconnect the USB and then go back in the software and configure your ESC parameters like enable reverse, change dead band, boost, turbo, etc. I didn't change much from the defaults except to enable reverse.
Your £11.61 120a ESC now has the latest hobbywing firmware on it and is totally configurable with the software.
Mine worked first time for my 10 min run time with 2s and a 7.5t. Hope you like it. My further quick impressions will go in the other thread linked above. I don't have too many unfortunately.
Zoea