Hey! I’m @Lil_SharkyBoy a 3D Artist and a Graphic Designer (self-proclaimed) on the platform. Well, to be honest I been working on the platform and using Blender for already some months and I have seen that actually the MeshParts reduce a little bit the lag compared to a large scalable building using Parts on Studio. Some examples could be a machine, this one could be made on Studio but depends on the level of detail you want to reach!
A smoothie machine I made for Venti’s Cafe
This type of things could reach a 3D Software and what Studio does not! As you can see the level of detail is high compared to what you can reach on Roblox Studio also, the tris count isn’t more than just 50,000tris in total! This is a really good optimization for just one machine and you get a really cool detail on it!!
Blender
I always recommend to use Blender over Studio for crops, decorations and other stuff since Blender is a 3D Software specialized on the modeling of 3D Object!! Why not use a specialized software for the task you’re requiring that? (If you get what I mean)
Anyway, when it comes to large-scalable buildings well… Blender has TERRIBLE collisions when exporting and importing into ROBLOX. Also if you would want to have your 3D Object with some good materials / textures when imported to ROBLOX you’ll need to actually use Textures and UV Unwrapping and other software for the UV Mapping Edition and etc, etc.
Studio
It isn’t fair that I just support Blender (since is my favourite 3D Modeling Software!) but Studio has his own benefits and con! First of all is that when it comes to simplicity you could just use Studio and make something great but simple (I’m not a great fan of simplicity)!
Also, I love the look that can take Roblox Studio when it comes to terrain and combination with Blender (crops), etc! An example could be:
Took me like 15min to make the lighting and the pose for my character lol.
Anyway, when it comes to more detailed stuff well… Studio starts to become laggy and our game performance decreases since +count parts -performance!
Well, if you want to know more about the pros and con of Blender and same for Studio, I replied some time ago to someone that was asking what was better, Blender or Studio.
Link:
Well, this is all what I can say to you but I hope you actually take this tips / info and make a good game with a lot of improvement on the optimization!