The Lockstate LS-523EN is the first safe I've owned. It was easy to install but be sure to check the opposite side of the wall you plan to use for installation. Electrical cables, conduit, romex, power boxes, etc. will surely play havoc with your installation if they end up being in way. Stud sensors work well for the studs but a quick look on the opposite side of the wall will pay for itself quickly in time saved.

As far as the quality of the safe itself, it seems quite adequate. The key pad is easy to program and works well. The actual dial you turn to open the safe seems a tad lame (as in not the highest quality) but again, this safe is intended to present a very low profile on the front side so that a picture or something can be placed over the safe and still hang relatively flush to the wall.

I will have to agree with the reviews I read prior to purchase, there is not a ton of room inside this box. But given the gauge of the metal used, the overall inside and outside dimensions of the box, the internal locking mechanism, battery compartment and the 4" space you are trying to insert into, you are still left with a decent amount of storage space inside. Intended use is the key and in my opinion, it's the price point for this safe that makes this whole thing work quite nicely.

Yes, the bolts supplied with this safe won't work with the wooden framing (2x4s) in your walls. If you have aluminum 2x4s then you might be golden. Otherwise, plan on raiding your spare parts jar in the garage or visiting your local Home Depot or Lowes for 4 decent wood screws.

At the end of the day, I am very happy with this purchase. I would do it again if I needed more safe space or end up moving to a new house someday. All the best.