I've never heard anything good about free standing bags. Are there any that won't easily break from the base or shift on the ground? If there are any decent free standing bags... Would it be possible to use outdoors and cover with a tarp when not in use? I guess a water filled base would be out of the question due to freezing, but perhaps sand would work?
I have a Slam Man and TBH I find it pretty ****.I have it filled with water because it's on my communal landing(so need to be able to move if asked) but any time I really start to get any power going it lifts off the ground. If it's your only option by all means go for it,but I don't know if actual free-standing bags might be better,and I've been told my SM would stay grounded with a mix of sand and water,but it's not an option for me. There are folding stands you can buy which might be better,but I always have something which takes financial priority,like my selfish kids wanting food.