The vision 4 uses different leds (crees of some kind I think). It might be possible to change these to mc-e’s but I suspect the current draw would drain the battery very quickly, that or you wouldn’t get a worthwhile improvement dues to how they would need to be wired.
I_Ache. I don’t think you can buy mc-e’s on 2S2P stars, so either you need to modify what you can get, or have 2 4S stars in parallel. Neither is a plug and play fit and would need some wiring changes (though the driver would not change). I think the simplest way would be to get 2 4S stars with pre mounted leds and run in parallel, this should mean the leds are central, the way I did it was a pain to get them centred on each star. Don’t forget the spacing for the face plate or your new leds will get crushed!