I agree and I've posted a video on my youtube highlighting the long load times.
watch?v=GSGZmknIGXw
Why there was no option to install is beyond me. It's as if Id Software looked at the 45 second load time and said...
"This is ok, we can ship this as is".
Another huge problem I have with the game is the fact the mapped the sprint button to the L3 button and it has to be constantly held down. Makes your thumb very sore after only a short time.
Id, please patch Doom 3 BFG Edition so we can install to the HDD and customize the controls to put sprint on the left trigger. There is no reason why the flashlight cant be on the unused circle button!