Hi Brandz
Burms are one of the snakes I have almost always had. As the dedicated slave to two large ones I'll try answer your Q's below
Are burms generally docile snakes or are they aggresive? - Generally docile can be a bit off colour at times, like when they are in the blue.
What is the average weight and length of full grown burms? - Depends on how much and how often they are fed. I have two 3 yr olds, both closing in on around 4m, f=9kg M=13kg
Have any of you personally been attacked by one of your burms? - Yes, Often. The female tries to take a swipe at me everytime i open her cage. She now gets a grab stick behind the head until i can secure her with my thick leather gloves on. Wonderful snake once she is out of her cage though
Do attacks on owners happen often?... not counting attacks caused by owners careless mistakes. - You answered your own question there.
What is ideal substrate for them? - Newspaper is the easiest. Dunno if that's the best, the way my female defectates and urinates, she gets a cage clean almost twice weekly... newspaper is definately cheaper and easier to clean up messes. Burms, especially large ones can really take power dumps...
What size enclosures do you guys with large collections of burms use when they are adults? - Mine are in cages 1.8m (L) x 0.6m (w) x 0.6m (h) made of strong wood and steel with sliding 5mm glass fronts. If they get another metre or so I'll consider getting them their own room, purely because I have the space for it.
Once the snakes reach 3-4M or so Do you feed them in their cage? - I have always fed them in the cages, as I do with all my snakes. I know a lot of people don't, but then I don't handle mys nakes unless they are ill or getting cleaned etc. I have dogs and cats to play frisbee with when i feel the need to bond to an animal.
If it is required to feed them in the enclosure, is it safe to feed on their substrate ?? - If they are on newspaper...
If owners are attacked, are the majority constricted or are they bitten and then left alone? - I normally just get a lot of puncture wounds. The male tends to bite and wrap a little, but if I sit still for 30-60 sec he reailses that I am not food and lets go. The female tends to strike a lot more viciously, thankfully she hasn't got a good grip on me yet. You will bleed. It is a bit uncomfortable, but no worse than nicking yourself shaving... a few times in quick succesion
What is the best method to get a constricting snake off of you? vinegar,hot water or unwinding from the tail etc - Sit still and wait it out. You are in no danger of dying from a large snake stuck on your hand.
And lastly, do burms generally make good and safe pets if cared for properlly ?? - I wouldn't get rid of them for anything! They are extremely easy to take care of, they do make awesomely large inhabitants of your house, and are generally gentle giants. They have good temperaments by python standards, and will eat just about anything you give them.
!!