V4.03 are basically the same, with the difference, that if you have purchased the 3D option you will have 3D functionality if you have installed V4.03. If you don't have 3D purchased then V4.03 and V3.13 will give you the same functions and options(=also called bugs).
Remember if you update to V5, your NavData.db will be encrypted after first use of V5
Ingo