Blast Match
½ " rod x 2"
Length: 10.2cm 4"
Width: 3.4cm 1.3"
Thickness: 2.55cm 1" widest
83.7 g (76.6g listed) 2.95 oz (2.7 oz listed) total
Coglin's Magnesium Firestarter
Length: 8.75 cm (3.05") ferrocerium -1/8" rod x 3"
Width: 2.85cm (1.11")
Thickness: 0.95cm (0.37")
Weight: 45.1g 1.59oz
Strike Force
1.9"x1/2" rod exposed
Overall length: 12.75cm 5"
width: 3.2cm 1.2" (not counting rib)
Thickness 2.2cm 0.87" (not counting rib)
Weight: 103.5g (104.9 listed) 3.65oz
Campers Village
1.8"x1/4" rod exposed
Length: 8cm 3.15"
Width: 0.95" widest (blue handle)
Thickness: 1.7cm 0.65" widest (blue handle)
28.9g 1.02oz
Anew (Davenport)
4" x 3/8"
54.7g 1.93oz
The differences in weights are not great. Perhaps the most important consideration is how the firestarters are to be carried on the person. The Strike Force is just too bulky to carry in a pocket, the Blast Match is almost too bulky. The ANEW can be carried in a pocket though a belt carrier would be more convenient. The Campers Village and Coglin's are easily carried in a pocket.
Note that the CV and Coglins are thinner rods and more difficult to start a fire with damp tinder. This is especially true of the Coglin's (1/8" rod). While the magnesium really works, and is easy to scrape off the block with a hacksaw blade striker - it's hard to get a pile where you want it with cedar tinder (it falls through), and in windy conditions - when it blows away.