YHVH = YHWH = Ja-Veh = Ja-Weh-Veh = Jahovah = GOD
I remember in the early 70s a JW told me that if we didn't use God's name then He would not hear our prayers. "If you were out in a crowd and you saw your friend Jack, if you yelled out, 'Hey, you!' then you shouldn't be surprised when he doesn't answer you. Likewise, we call God by His name and thus we identify Him, and thus He knows when we call out to Him."
But there's a big difference between pronunciations. Shouldn't we get as close to His name as possible? For someone who's omniscient, wouldn't He know when we're addressing Him? There also doesn't seem to ever being a time when His people called him by name. In fact, wasn't it punishable by death? Abraham didn't do it. Moses didn't do it. Peter, James and John didn't. So why should we? Even if we call out to our friend, "Hey, John!" -- it might be John, Juan, Jacque or Jack. If it's important to call HIM by name, we should get the name right, or as close to the Hebrew as we can get.
But seeing that Jehovah was actually Jesus just adds more confusion.