By almost all accounts, the MN-18 design is the UEPC's first serious efforts into dealing with space warfare. It was the first real design based from the spine-up to operate in microgravity environments. Though it was poor compared to its adversaries on the moon, it was significantly better than using KR-14s, which had been designed for ground warfare and were hardly maneuverable in space.
The MN-18 has fulfilled the role of space attack axel largely to satisfaction, though glaring problems remained evident as the years went on. This wasn't to say that the MN-18 was outclassed, but it was clear that other Axels could take advantage of the MN-18's fragility and construction to defeat them. Simulated combat ratios approached equal odds when the curve of difficulty of simulated opponents was matched against equals in MN-18s. Generally, a pilot had to have three years worth of experience in an MN-18 to equal an OU-8 operated by green pilots.
Aware of this problem, an updated design of the MN-18 was conceived to answer the problems and create a better-functioning space Axel. Though some of the structural modifications are radical, it was always classified as a different model of MN-18.
With the stalemate against the moon, the 'V' version of the Ikida was put on hold. Only a pre-production run of five machines was completed as proof-of-concept vehicles, and were assigned to Space Station five.
All of this changed when the UEPC cleanup effort at Palifca turned for the disastrous. One prototype machine, piloted by an Agitator, ruined several squadrons of MN-18s and destroyed two full carriers and a frigate. Such tremendous losses of manpower and material at the hands of one machine was unacceptable. The MN-18's was immediately halted and the new V model was rushed into production. Aside from some minor modifications and tune-ups to the original plans, it is the same design conceived a decade before when the MN-18 was facing performance problems.
The V model is a relatively new machine, but handles a lot better than the MN-18 and is accepted as being a faster model. The cockpit pod has been increased, and while it makes for a bulky target, it contained additional shock protection to keep the pilot comfortable during high-speed maneuvers. Better targeting equipment through the redesigned head model (Adapted from the Bulava-B) allows pilots to use thermal imaging and color, instead of being restricted to the basic unit carried over from the KR-14.
The unit has yet to see combat. Fresh MN-18Vs have been deployed to several orbital stations, though they are mostly being distributed from Space Station Five. They have yet to see battle against the Lunar Units, though the MN-18Vs carry the same armaments as their predecessors (laser cannons, small-arms rifles, rail-guns, etx.)
(Had a sketch of this for a long while, since I thought the MN-18 was too spindly, but none of the sketches I liked. I guess that page from Yamashita's book did wonders eh?)