If I were a shitty GamePro writer, I'd probably start a review for this game with a quote along the lines of, "With Gun Hazard you'll have no worries of it being a Fun Hazard!". GamePro is fucking stupid.
Gun Hazard, however, is not.
Front Mission: Gun Hazard is a side-scroller mech based RPG in the vein of Cybernator and Metal Warriors, based in the Front Mission universe. You have the typical RPG leveling up, as well as monetary gains and purchasable upgrades. The missions are pretty straightforward, you walk to the right and shoot whatever you see. It's enjoyable for what it's worth if you enjoyed the other two side scroller mech games made by this dev team.
Here's a picture of the map screen, you navigate between missions and shops with it.
Here's a picture of the game in action. It's pretty nice looking for a SNES game and has a lot of multilayer sprite fun going on.
If you like mech games and light RPG elements, check this game out.
Oh, and one more thing: Unless you can read japanese, I'd suggest you get the translated version.