Is it adviseable/possible to make all/some of my models in HL2DM func_details? Also, Should I make the brush faces that cannot be seen by the player into nodraw or hint brushes? I have lots of building facades in my map that were made from brushes.

I also have things like building models and fuel pump models in my map. The gas pumps are prop_statics right now. Just trying to reduce compile time and increase in-game performance.

I've read lots of threads on these issues but it seems that people have different opinions and I just need it clarified before I scour my level and change tons of brush faces. on a side note, my current map .bsp size is almost 10 mb. Thanks in advance.

Well, they only cause splitting if an edge of a func_detail lies on the same plane and touches a regular brush face. If you have a small fiddly bit and place it on the middle of a big wall it's not going to chop it up, but if you have a broken wall on top of a regular wall and they are perfectly aligned they will.

The problem is when people just blankly say func_detail doesn't cause face splitting, as it most certainly does in the right situation.

Well I noticed it while working on my map. I had two types of doorways, a regular and a combine one. The regular one fit perfectly into the wall so nothing was sticking out while the combine one was slightly slanted so that one of the two edges was sticking out over a big floor brush. The regular one cut up the nearby floor on both edges while the combine one cut it up only where the one edge was aligned. The one sticking out did nothing. Then with my knowledge of the old engine and some experimentation I pretty much figured it out. When I get the time I'm going to write up a tutorial about proper func_detail usage and suggestions on how to avoid the face splitting.