We just went through immigration yesterday in Denpasar. We landed around 2:20 pm and were among the first off the plane. We hustled to purchase our visas (as that was the delay last time) and were met with no lines. Then we saw the immigration lines. OMG. I have traveled the world extensively in a number of developing countries and have NEVER seen anything like these lines. Until now, Moscow airport was my all-time worst delay - 45 mins.
We spend OVER TWO HOURS IN LINE. The lines would go for 3-7 minutes without moving at all, then would move up an inch.

They are NOT doing the fingerprinting or the taking pictures of visitors - they just don't have enough people to handle the rush periods, and the people they do have are "new" according to one official and amazingly slow. On top of that, the line has little air conditioning; at one point, a small child was carried out by her parents from fainting - the immigration officials gave her a bottle of water and hustled them through.

The immigration lines in the non-tourist visa area seemed much shorter - if I had it to do over again, I would go get a regular Indo visa.

Be warned and prepared... bring cold water and lots of patience. And stick towards the middle of the queues instead of the far right or far left. They seem to have more people handling each line in the middle.