Ok, I've read a few posts; certainly not all of them, but I disagree with what I've read so far.
Plain and simple, the .327 magnum was mis-marketed; badly.
They aimed it at the buyer in need of a SD cartridge, and largely ignored the sport-shooter crowd. When they finally offered it to the sport-shooters, they offered it in firearms that compete with more common, and more powerful cartridges.
I.E., it was first offered in snubnose revolvers, and it competed with the .38 special and .357 mag. Performance is said to be between the two. With the cost and (lack of) availability of ammo, most folks just went with the time proven two that the .327 competed with.
Then when Ruger finally "woke up", if only slightly, they offered it in a full sized SA Blackhawk, and a GP-100. Again, they're placing a smaller cartridge to compete with larger calibers in the same gun. With the option of shooting .38 specials or .357 mag ammo, most folks won't opt for the smaller cartridge(s) that can be shot from a .327 magnum.
Quite honestly, they should have offered it in a Ruger Single Six. Reason? Then it's competing with smaller cartridges in the same sized gun. A Single Six is very packable on the trail; more packable than a Blackhawk, for sure. The added power offered by the .327 in this small framed SA revolver would appeal to me, as well as other shooters. Perhaps S&W should have offered it in a longer barreled J or K frame for the same reason.
As it stands, I'm still very interested in a .327 magnum. I'm just not interested in it in the platforms that the firearms manufacturers are offering it. If I buy a GP-100, it's going to be chambered for .357 magnum. Ammo is far cheaper, and with the ability to shoot .38's, which are also highly available, I don't want one in .327 magnum.
And if I'm buying a SP-101, the same idea applies. If I'm buying a J-frame snub, it'll be in .38 special. With the price and availability of ammo, the manufacturers shouldn't try to make the .327 mag compete with these two.
The day I find a Single Six in .327 mag in my gunshop, I'll take it home with me. Until that day, I'll stick with the older and proven cartridges. I'd also jump on a K-frame Smith so chambered, as long as it has a ~6" barrel. Such a gun would seem very useful to me.