IT IS strange that the SL, which is the most luxurious roadster in the Mercedes-Benz range, is one of the last models to be fitted with the new AMG 6.2-litre V8.

After all, you would think that customers who pay more than $380,000 for a car expect to have the latest and greatest equipment.

Fortunately, we can honestly say that after test driving the SL63 AMG that it really is worth the wait.

Of course, a car that costs this much money is almost certainly going to be a very impressive machine. That said, the 6.2 is without doubt an excellent engine and the drop-top SL allows you to really enjoy it.

The brutal sound of the exhaust note as the car thunders forward with stunning force is up there with any of the best automotive soundtracks you'll ever hear. It is best enjoyed sans-roof, but is also quite audible when you have the roof in place and windows up.

The new blipping downchange feature also sounds fantastic, as does the gruff rumble of the exhaust after you back off the throttle and let the engine run down.

What's not surprising is that the SL65 AMG is a very, very fast car. There is a mesmerizing powerband that runs all the way to the redline. Of course, you only get to use a tiny part of this vehicle’s potential, but even that is good fun.

The SL feels larger and a little less stiff than the excellent SLK, but it was still very well composed on the test drive this week, which was held on some pretty bumpy roads.

In the case of the SL63 especially, it is a car that you can go very fast in quite easily. It slings from one corner to the next and your biggest concern is whether you can wash off enough speed for the next bend.

Luckily, the brakes are more than up to the task and are able to wash of all the extra speed.

You can spend a lot of fiddling with the various driver assist modes. We selected the ESP Sport mode which effectively allows the car to slip a little, but the system comes into save the driver (and their investment) if things really go pear-shaped.

You can also flick the adaptive damping system onto Sport mode. This does sharpen the ride slightly, but the standard setting is pretty good to start off with.

There is also a launch control feature and a new AMG button. Just like the M button in the BMW M3, the AMG button brings up a full raft of settings that you have previously determined. Given there are so many settings you can fiddle with, this system could save you a lot of time.

The first car we drove was the V8 SL500, which was a little underwhelming, to be honest. It is still a nice engine, but the revised V6 is not all that far off in performance.

Okay, it is 0.8 seconds faster than the V6 to 100km/h, but the difference doesn’t feel huge when you are out on the road. And for a 5.5-litre V8, it doesn’t sound as special as you might expect, especially with the roof up. Under heavy acceleration there is a lot of induction noise, but not all that much of an exhaust note.

The SL350 has had its engine note improved quite significantly and it really does sound rorty, even at low speeds. And the extra punch brought about with the changes is welcome.

This model feels more like a sportscar than the car with the previous V6, which did feel sluggish at times.

At more than 1910kg, the SL is never going to win any speed records with a six-cylinder under the bonnet, but it is a comfortable car with performance that many customers will be more than happy with.

The automatic transmission is smooth when left to its own devices, but take over and the manual shifts are also relatively quick and smooth.

It is hard to tell how different the new steering system feels to the previous set-up, but we can say the new system works quite well. The weighting is naturally quite light at low speeds, but binds up at higher speeds.

The SL63 did pass on a lot of vibration through the steering wheel on some coarse-chip roads on the drive program, which could be related to the tyres.

Otherwise, our drive in the revised SL reminded us how well-suited the big topless Benz is to comfortable cruising. Such is the quality of design that, even with the roof down, you can drive at quite high speeds and still maintain a conversation without having to raise your voice.

There also a lot of room behind the customers and a pretty big boot area, compared to other roadsters.

Inside, however, you'd be hard pressed to pick the difference between this and the last car. Mercedes borrowed a page from Subaru's book by installing a new instrument cluster with illuminated needles that spin around the dial and back into place when you first switch on the ignition.

It is a nice touch and the new instrument cluster looks good, but these are all minor changes.

We like that the Airscarf system is standard on all models. This system blows hot air onto the back of your next, which is a great idea for a convertible that you would like to take out when it is not so warm. Of course, it's also nice to have heated seats.

It's a subjective thing, but some people will love the new look and others will instantly wish they had bought one of the last-generation models with the quad-light front-end. The new headlights can look good from some angles and goofy from others.

While the upgrades across the range are welcome, price rises as much as $8000 across the range, will be hard to swallow - especially when the proposed luxury car tax hike will also make these cars even harder to afford.

While they will never be described as bargains, most of the SL models live up to expectations of buyers who want impressive performance and comfort in an elegant top-down package.