New 2015 Mountain Hardware Ultra Lamina with zone mapped insulation

These new bag-series is called Hyper Lamina, BTW.

A center-zip is one of the new trends for sleeping bags in 2015.

"Another problem with the center zip is they only make half zippers so there is no way to ventilate the feet. I think Mountain Hardware made a mistake. If you are going to do a center zip, make it full length, It is not even a new design."

Couldn't agree more. With MYOG bags, and unlike commercial ones, I use a full length NON-separating center zipper, and just add another reverse slider at the foot so it can be opened for ventilation. The separating zipper on my MontBell spiral 3 tends to come apart when exiting in the middle of the night, and is a PITA to get back together when half asleep in the dark. But it's tough to beat a 30 degree bag for 20 oz, so it's the one I use in the spring and summer.

My first bag was a 3/4 length center zip down affair that my Dad had in WWII. It had a separate cover that was very heavy with a kapok life preserver attached that blew up with a small CO2 cartridge. The cover got left at home, but I liked the center zip because it is easy to access when getting up or lying down on my back, and rolled with the hood to left or right with me as a side sleeper.

Yeah, Golite years ago came out with the down bag called the Feather and it had the short center zip. It lasted a year and they all went on discount at Sierra Trading post because you could not ventilate the bag. A failed experiment and now Mountain Hardware is giving it the old college try again. Will see how it works for them.