I agree that that tactical vest is probably overkill. Operators in the field here in Iraq carry less gear!
I can't speak to the quality of that vest, but if you MUST get a load bearing vest, I would look to the MOLLE vests that the military employs. Of course now we put most of our gear directly to our body armor, but the MOLLE VESTS are great because the are separate from the body armor and you can wear one without the other. They are well designed, rugged, and versatile. You can attach and remove accessories quickly and easily.
As far as the cross draw holster on the chest rig, it's very popular but I personally would get a drop down leg holster to take some of the weight off the chest and put it on the thigh. Your legs are the strongest muscles so distribute some weight there (handgun, a couple mags, knife, flashlight, etc).
The bigger question though which has been asked is WHAT type of scenario are you expecting? In most disaster scenarios you are better served by just locking down your house with supplies and waiting it out. But if you have to leave, you have to be realistic and consider that in a disaster scenario where you are on foot you are only going to be able to carry about 30 lbs for extended periods if you are in good physical shape. I'm in darn good shape and my load bearing limits for just purely marching is about 50-70 lbs for a few hours - and that's with me consuming massive amounts of water and energy foods, exerting all of my energy, and being physically useless in a fight afterwards and exhausted for a full day. If you don't have experience with this, fill up a camping backpack with some gallons of water or heavy objects (books may get wet from your sweat soaking through) and go for long walk. Take plenty of water and energy snack foods.
I made several lists of critical disaster situations that would cause me to go out on foot vs. driving and what I would pack in either case. For vehicle bugout, I have a 4Runner and included rifle, mags, extra gas tanks, and tools for off road because I expect roads to be clogged. I included ax, saw, shovel, bolt cutters (for fences), MREs, and several large water containers.
Start writing down critical needs such as high energy foods for a week (nuts, protein bars, trail mix, etc.), water (several gallons) and water purification system/tablets, small first aid kit, small shelter, clothes (clean socks and underwear), medical needs, small hygeine bag, small knife, and a handgun with a couple mags. You will quickly accumulate weight and soon start realizing that much of that tactical gear is useless weight. For most average people, I would say that 20-30 lbs is their load bearing limit and you can't fit much in a 20 lb load. I also have two dogs, and have dog "backpacks" saddles for them so they can carry their own food and some water. To this end, I would just suggest a well designed internal or external frame camping backpack and a concealed handgun so you are as low profile as possible. Also, comfortable water proof breathable hiking boots are a must. Break them in and then store them with your gear. The high profile tacticool ninja is probably going to be the target of police, national guard, and reservists trying to 'restore' order and also of the thugs and gangs - only they will shoot you long before you see them coming.