This is the one of the most useless ships in game because of terrible low speed.
If you use and outfit it right, it's far from useless. It's not great in say a high intensity CZ, but many small ships aren't either. Sure, it's one of the slowest ships around, but using the fitting I've posted above, along with some engineer mods to the seeker missiles, I've been very successful using the MK.4.
For it's price and size, it's one of the most versatile ships in game, even if it is as slow as molasses. That being said, it could use some love. One more utility mount would be a godsend to completely round out its usefulness. Even at 209m/s (300m/s boosting) other ships have a very hard time outrunning its missiles unless they already have significant distance from you. Since it slow to turn, the three turreted multi-cannons on top make it hard for more nimble ships to avoid a constant barrage of fire. I've been able to engage basically any rank/size of ship with little effort. Some are harder than others, but if I play it smart I can take out just about any ship.
With the kinetic/explosive loadout above, one only needs to keep 1 pip in weapons for constant fire and can even get by with 1/2 pip for a decent amount of time. The seeker missile (thermal cascade/rapid fire) cook other ships if their shield are up, especially if they decided to use SCBs, and once the shields are down will completely strip the drives and hard points, making the target absolutely dead in the water (vacuum) to be finished with multi-cannons.
I get that some people may not like it, but it's far from useless when there's a skilled pilot in the chair.
I would 'like' it to be faster, but my main gripe with it is the fact it only has 2 utility slots. Just stick one more either at the stern or midship above the cockpit and it'd be golden.