TerrainRegions effect on performance?

My game features maps that heavily use terrain. Until today, all the terrain was in the workspace all the time, and just the parts and meshparts were being loaded in and out of server storage at needed time.

Today, wanting to optimize the game more, I copied different terrain chunks for each map using terrain:CopyRegion(), and when loading map, I am now from script loading only the terrain chunk of that map, using terrain:LoadRegion(). TerrainRegion instances are under ServerStorage.

My question is: Does this improve performance, make it worse, or not affect it at all?

roblox automatically unloads and reloads terrain at further distances, and if at max graphics lowers the quality of the terrain at further distances instead of unloading

No it doesnt. It does so only if streaming is enabled, which in my experience is not, because roblox streaming is horrible + that wasnt the question, I am asking how heavy is TerrainRegion instance on performance.

then if you want to do it that way then fine, you will just have to keep it optimized. terrain saving and loading shouldnt lag out a ton if you optimize it

i do saving and loading for water meshparts and i dont have to change anything to the code to make it not lag