This replacer uses the existing trunks of the vanilla model in order to avoid clipping and preserve Bethesda’s vision, only enhanced and 3D. The geometry of the new models is about 5-10x more complicated than the vanilla ones, however, there is far less transparency/overdraw than the vanilla models which should offset some of the performance cost. This single mod won't affect performance however (0 FPS loss on 3 different computers of varying quality). FPS loss could not be measured until vertex counts were well over several hundred thousand, which is many many times greater than this mod.

For reference: Mod vs Vanilla
Pineshrub01: 3960 vs 596 triangles
Pineshrub02: 5937 vs 1419 triangles
Pineshrub03: 2303 vs 606 triangles