I use what I've got, which are certainly not the best: A Coleman Xtreme 50-60 qt (not certain what the exact capacity is, but it's in that range). An Igloo 100 qt. And a handful of Coleman beverage "stackers".
There have been many more over the years, but they weren't worth keeping, or died horrible deaths.
The Stackers are terrible. You're doing very well to get ice to last a day. I rarely use them any more, except when I need to try to keep things from freezing.
The large Igloo is primarily a meat transport cooler. But I use it for whatever is necessary, whenever it's necessary.
The Coleman Xtreme is my go-to, do-all cooler. The 5-day claim is pretty fair for ice and use by adults. In cooler weather, with responsible use and placement, I've still had remnants of the original ice after 9 days. No matter the weather, if children are always sticking their grubby little hands in the cooler and leaving the lid open, 2 days is pretty optimistic for ice.
You can always stack the deck in your favor, however, no matter what you use:
Pre-chill your cooler before you load it. I usually add 20-40 lbs of ice to my cooler(s) the day or night before I intend to load them. (The water will be drained, and the ice will stay on for the ride when food is loaded.)
Use frozen bottles of water, instead of ice cubes. No water, and less surface area to melt.
If you know you'll be gone 3+ days, freeze the food that you won't be getting to for a few days. Freeze your meat. Take smaller containers of milk and freeze all but the first one you'll be using. Etc...
Keep them in cool places, and shaded. Throw blankets or other insulation over them, when possible.
If I know I'm going somewhere I won't want to come back out of until the trip is over (meaning no ice runs), or I'll be battling heat for some or all of a moderate-length trip (5-9 days), I pre-chill with dry ice and add 5-10 lbs on top of the food after loading.
(Just don't over-do it. I've frozen the entire contents of my cooler before, by using too much ice on the bottom and dry ice on top. We still had ice at the end of an eleven-day trip, in the high desert, in early September, though...

)