I think that Borneo Short Tails are amazing pythons and that in the correct hands can be a wonderful animal. I have some myself and am getting ready for my first breeding season with them. That being said I would suggest that you think very hard about this. Borneo are by far not the biggest of the Short Tail Pythons but can get large, and coming from someone who has owned Retics, Burms, and Boa Constrictors, you will not find a species of snake that strikes harder than the Bloods (Short Tails Included). During feed day my big female hit the front of her Boaphile cage so hard that she actually popped the door open while it was latched.
I have raised all my Borneo Pythons from babies and it can be challenging to say the least to give them the time they need to grow up tame. They have a very strong feeding response and if even the smell of food is in the air they are hunting. They can also be very quick to defend themselves and they put all their body and energy into a strike. So if you are not very experienced and have never handled an aggressive snake I would turn this down. I would hate to see you or the animal get hurt.
Don't get me wrong, Borneos are great and I love mine to death. But I can honestly say that I have spent thousand and thousands of hours with mine and I still don't take them to educational presentations that I do because the slightest things can sometimes set them off.
The decision is ultimately yours, but do think very hard and don't rush into a situation that you may not be prepared for.