Hey, I have the vachanger3 and have hung up to 14 lbs with it no problem. I have read of people hanging up to 16 lbs with it. I am not sure if you need to hang any more weight than that with a vac-hanger because it is a different design and set-up to compression hangers. You can get pretty awesome fatigue at relatively low weights with vacuum hanging. For myself, I found the 10-11 lbs mark was awesome for gains and feel when I just used the vacuum cone. I preferred the set-up of just the vacuum cone to applying the sleeves with it.
I have not used the LG hanger but it is an awesomely made device. Looks and sounds really good. However, the claims of being able to hang 25 lbs+ with it are not really necessary for 99% of hangers. That is a sure way to get blisters and mess up your glans.
If you are hanging currently and are having no problems, and are still gaining, I would stick to that ;)