I'M SURE you are all familiar with the cartoon hero Superman - by day he is the mild-mannered reporter Clark Kent but by night he cruises the skies in his blue tights and red pants as the original superhero.

Why, you may ask, am I introducing our latest addition to the long term fleet this way?

Well, if our current long term Rover 75 is Clark Kent, then our new MG ZT 190 is definitely Superman. The worthy 75 seems to have undergone the superhero transformation in a phone box and come out all pumped up and ready for action.

Evidence of the change is clearly visible, although not quite as tacky as red pants and blue tights.

The MG sits much lower than the standard 75 and rests upon a set of fat multi-spoke alloy wheels. At the front the mesh grille, extra driving lights and deeper spoilers all hint at the extra performance on offer. At the back, a boot spoiler, twin exhaust pipes and chequered flag badging set this model apart from the more sedate wagons that roll out of Longbridge.

And inside, the swathes of classy wood and cream dials have been binned in favour of a more garish finish - aluminium effect panels on the dashboard and some blue flashes on the seats (which are in questionable taste).

But the best thing about the transformation from 75 to ZT is the mechanical tinkering that has gone on. From the moment you turn the ignition key you know this is no ordinary 75 - a throaty growl emanates from the rear as the V6 grumbles into life. (My colleague Simon Harris described the engine note as 'saucy' and I think he's hit the nail on the head.)

Once you get used to the long travel clutch, progress is very quick indeed - 190bhp offering the potential for plenty of fun. But this is not fun in a revvy kind of way. The V6's characteristics offer plenty of torque but the clutch and gear ratios mean this is no sprinter - think of it more as a middle distance runner and you won't be far wrong. This is borne out in a comparison with a Skoda Octavia RS we had on test.

The Skoda's turbo power delivery ensured the Octavia pulls away faster initially, although the long-legged MG claws its way back into contention once it's up and running. And because this is quite a heavy car, don't expect stunning handling - the ZT is surefooted but it can feel a little put out when you want to get aggressive on the twisty stuff.

For £20,495 on-the-road, the ZT offers you plenty of power for your pounds - although I thought charging £275 extra for rear electric windows was a bit on the stingy side.

For the money, there are plenty of performance models on offer to tempt you away from the ZT - the Honda Accord Type-R and Subaru Impreza WRX being just two.

If out and out acceleration and handling are your bag, go for either of these two. However, if you like long-legged performance with comfort thrown in, it may be worth taking a closer look at the ZT.