For as long as there have been stompers, there have been stomper clones. While they tend to enjoy limited success, it's hard to argue with the fact that the original stomper competitor, LJN's Rough Riders, were the toughest competition they ever had. Just like stomper, they diversified over the years and had playsets, but also went that extra step of branching in to pop culture. With tie-ins to A-Team, Magnum P.I., Knight Rider, The Dukes [of Hazzard], Smokey and the Bandit, Dune and possibly others.
When Rough Riders went from on/off to 3 speeds, this was called Tri-Ex. They also had Water Divers than ran underwater. They even swiped the wheelie action from Stomper. I tend to forgot that the Rough Riders conical hubcaps allowed them to drive on their sides.
They even had a line of military vehicles. It was called Marines at first and then it was called O.M.N.I. Force with OMNI standing for Official Military Night Invaders. Since the Marine Corp name is trademarked, I'm guessing they got creative and came up with the OMNI name to replace it. Both lineups consist of the same 6 vehicles: Invader Command Jeep (6431), NX Missle Launcher (6432), N-70 Assault Tank (6433), Tank Gunner Attack Truck (6434), Mobile Radar Tracker (6436) and Ground Commando Half Track (6437). The biggest difference was the change from camoflage coloring to a straight green color. Well that and the name change on the graphics of the vehicles. Omni also added a helicopter (6447) that was just a green version of the grey A-Team helicopter that could pick up and release a vehicle.
I can't say I remember them, but LJN made Rough Riders Switch Force where you "press the secret switch" and it becomes a battle vehicle. I want to say it seems like it's trying to compete with M.A.S.K. but it's funny that they rip off the transformers tagline and go with "more than they appear to be!"
The people who owned most of LJN also bought Matchbox and eventually merged the companies. If some random website quoting a book is to be believe, this parent company started selling LJN toys under the Matchbox name in Europe. This would explain the backstory of Retromash posting this 1984 matchbox catalog here where pages and 54-58 are dedicted to rough riders. This was a British catalog so it adds some credence to this development. It also explains why the packaging was printined in English/French/German. Plus, of the handful of images I've found, most have European price tags on them. The only problem is how this jives with other stories about the history of LJN but I'm not going to worry about that here.
The funny thing about having matchbox branding is that eventually Matchbox Power Scouts would come to be.