Thank you Mr. steaven for the answer. I did tried to install the update but failed, both via TWRP and Stock Recovery. As you said the new thing from this update -for now- is only modem.img (v20 >>> v23), well it's okay if i can't install the update. Someone with 4gb who succeed for installing this update just share the modem.img file. I using this modem v23 for almost two hours now, with the same cellular provider when i am in v20 and it seems v23 is not get any better than v20. If you don't mind, i will share my review a little, Here is my conditions I live in Indonesia, in Borneo Island. I am using cellular provider 3 Hutchinson Indonesia (both SIM Cards) At this time around 9 - 10 PM at night here, weather is light rain and a lot of cloud. V20 SIM1, stable at H or H+ around 1bar to 3 bar signal. Outdoor is 4 bar as long as its not heavy rain. V20 SIM2, stable at 3 bar when indoor or full 4 bar when sky is clear or when i am on outdoor. But when in the weather is like this SIM2 -almost- never lost signal, at least it stable at 1 bar) V23 SIM1, little bit similiar compare to V20 V23 SIM2, almost never got any signal at all, i got 1 bar signal maybe just for 1 second or two and lost it again. Maybe result can be different depends on provider we use, and weather also. Let's see how far this V23 modem can go when the tonight sky is clear.