You'll get much better performance (e.g., insulating value) from a hard-shell cooler than a soft-shell. Soft shell coolers are primarily radiant heat reflectors, with little insulating value. I also find that they quickly develop leaks, making things messy when used with ice.
I completely agree. Cold packs are better than ice when using a soft cooler but they aren't as good as hard coolers for keeping things frozen or cold. We've got a Coleman 5 day cooler that is awesome. We've had it for about 6 or 7ish years now and we still have ice left when we get home from a week-long camp, even in heat in the high twenties. (C)