Sounds good NY Biker - and I think your front door will be fine as you've a metal frame and you keep it deadbolted. I purchased the wall-mount and paid a handy-man friend to install it for me so I would know it was mounted properly on the studs. I'm very happy with that setup, and it sounds like you've worked out something that will work for you. It does help to have your trainer teach you some suspension exercises so you know your form is correct. The foot cradle is quite different between the TRX and Jungle Gym, but I prefer the latter anyway. Not that I can use that yet so I don't overstress that knee.

Have fun and let us know how you like it!