No question about it, they do tend to dry or congeal faster than other brands. I store mine upside down to curb this, but it really doesn't stop the process altogether. Doubly so for the acrylic versions.
I had the same problem with Floquil Polly paints too.
As mentioned above, Tamiya paints seem to be the front runner in the longevity department. I have some that are well over 8 years old and still fully usable.
Humbrol, in spite of their funky tins packaging, will last the long haul if properly sealed up too. I believe they have recently changed the container to a screw top, no?