Having just received the Guzzi Tech Diagnostic tool yesterday and hooking it up to my 2022 V85TT Travel, I'll say this about it. It works to get rid of the service wrench and will do a few useful things. Is it worth the $500+ I paid for it? For me probably yes, as I'm a tool guy and like have the right tool for the job and I absolutely hate hate hate taking my vehicles to the dealers where they are usually worked on by the most moronic chimps the world has to offer.
Something the tool wont do that I wish it would, is pair the OEM TPMS sensors to the bikes dash or ecu.
Things the tool will do that might be useful for the Guzzi home mechanic are:
Turning off the service wrench
Activating the ABS pump
Being able to check all the switches on the handlebars to make sure they're working when pushed
Activating certain systems like the fuel pump and brake lights to see if they're working
Activating certain warning lights on the dash
Viewing live data, which there's a lot of
Checking for and erasing any stored fault codes. Although this can be done with a much cheaper $12 adapter cable and $25 wireless OBD reader.
Things to keep in mind, this $500+ tool is not like using a Hex GS-911, for anyone familiar with using that tool on their BMW motorcycles. This Guzzi tool isn't as simple to use and comes with very little instructions, so trying to figure out what to select to do what you want will take a bit of button pushing.