I actually uploaded the wrong file for the lowpoly, try downloading it again. The changes are just some reductions to the polygon count and padding for the UVs.
You could use nurbs curves as an intermediary for this. Select the edges you want, convert to curve, and then revolve that curve, setting the output to polygons.
Also the faster the player moves the more textures they will be loading in a short time span. As this happens the textures cost begins to outweigh the polygon costs.