Can the Lite be updated to V4?
Yes using a friend's remote.
You need to find someone with Deus remote and get ready for the real McCoy version 4 update.
If I didn't live so far,,Inwould come and update your unit for you using one of my remotes.
You will need to supply your coil and headphone module,,just remember.
Also when you do update your Deus lite version,,get the person doing to load you a program with silencer set to -1,, actually let them load 3 programs,,one with reactivity 1,, one with 2, and one with reactivity 2.5. (All loaded also with -1 silencer setting)
Here is some thing I don't know,,as far as version 4,,if there is no Deus factory program with default reactivity set to level 2.5,,,,even if you update your unit,,and DON'T add any new programs,,,you won't have access to this new reactivity setting.