Since the company is embarrassed about publishing its specs (like voltage and mAhrs), I will stay away.
But Looking at what they do claim: 30 hours of talk time on a cell phone.
Analyzing:
1. A Nokia 2760 uses a standard BL-4B battery. They claim 7 hours talk time. The battery is 3.7V @ 700mAHr or 2.59Whr. To go 30 hours, let’s multiply that Whr x 5 to get 35 hours talk time; or 13 Whr.
A Lithium AA is 2.9Ahr or 1.5x2.9= 4.35Whr; so we need 3 or 4 lithium AA’s to run this phone for 30+ hours.

Now I get my lithium AA’s at Sam’s club for $1.67 each or $6.68 for 4. This company wants $20. So they will have to cut their cost by 4 to make it tempting for everyone.

2. If only ½ the charge of the fuel cell is used and then stored for a couple of months--- well that went to waist.

3. Another option is buy five 2500mA 1.2V NiHM batteries. That would give you 30 hours after 1 charge! And they can be recharged 500 more times and each battery costs $2.00 and a decent charger costs $10.00

Just my thoughts.

-Barry