Just received the Godox TTL AD 360II and X1-c radio trigger set. Tested them with a 5DmII and 5DmIII.
First issue I found is that the X1 "Gr" mode, just like Canons Wireless RT <Gr> mode, is not useable with older (prior to 2012) Canon DSLR's. When the "Gr" mode is selected with the 5DmII the Wireless mode switches from the "Gr" mode to the "All" ETTL mode (non Gr). This is verified on page 23 of the X1 users manual but it is not mentioned in any advertising that I have seen nor is it mentioned on the Godox website. Kind of a handy piece of information to have so if you have an older DSLR and were looking at the X1 system to have the ability to use the <Gr> mode, look elsewhere.
Second issue is that when using the 5DmIII in the "Gr" mode, the flashes will not fire. When the Slave group, in the X1 transmitter, is set to Manual mode in the "Gr" mode the flash output is changed and displays in the Slaves display but the flash does not fire. When ETTL mode is selected the flash will fire a preflash but then does not fire during the exposure. The non Gr "All" Manual and "All" ETTL modes seem to work fine so I am a bit perplexed about why the "Gr" mode does not fire the flashes. I have contacted Godox via email to see what they say so will update later with their response and what is causing the issue.
HSS is an automatic feature and is non selective. When you select the Radio Slave configuration in the AD 360II, HSS is automatically selected and the same happens when placing a TTL flash in an X1 receiver. This is a nice feature so you just shoot and no matter what shutter speed you choose the system just follows along. Worth mentioning there is no Wireless "rear curtain" sync with the X1 system.
What has struck me as odd is that, even though the AD 360II has the same 32 channel 2.4G radio transceiver as the X1 and that the X1 can directly control the AD 360II, their Wireless features are different. The AD 360II has no Master "Gr" mode and only has 3 total Slave groups as does the new Godox TT685 shoe flash. This means that when using the X1 in "Gr" mode you will not be able to use an AD 360II or TT685 in the D and E groups unless you attach a X1 receiver to them. May not be a big deal but again is worth mentioning.
More than likely I am going to ditch the X1 system and just continue to use the Ad 360II with either the Yongnuo YN-E3-RT/YNE3-RX or with the Phottix Odin system which I already have. The X1 does have flash sync delay timing so it will be interesting to see how well that works when Hyper syncing with Studio strobes. The X1 system would be something to look at for someone who does not already have a TTL radio trigger as cost wise, at around $85 for a transmitter and receiver set, it is very competitive especially when you consider the features it offers.