I am considering getting a heavy bag for myself since my boxing gym is only open twice a week (yea, it sux). I dont have anywhere to hang it inside, and theres a pair of trees outside that i was thinking of hanging it in between. The bags I use in the gym are 80 and 100lbs but they swing around like a child on a swing set when I hit them. Anyone know where i can get a cheap but reliable heavy bag and whether it shud be 150 or 200 lbs. I want to build up my power so i think im gonna go for a 200 pounder.