
Mercedes SL 55 AMG
Why 3.5: A supercharged V8 sofa — magnificent torque, zero feedback. Bought new by wealth, bought used by optimism; the depreciation curve tells that story.
Layout
Natural habitat
Ride comfort
Sound
The M113K's Lysholm supercharger whines over a lazy 5.4-litre V8 rumble, and at part throttle the blower is the most interesting thing you hear. But it is silenced for seafront duty and stops at 6,500, so there is no top end to build towards.
8-cylinder · supercharged · 6,500 rpm redline · rated 6.1 / 10 for engine sound
Market value
Median asking price, good condition · €55k (2008) → €39k (2026), trending down · illustrative data
Child seats · ISOFIX
There aren't any — strict two-seater.
No ISOFIX on the front passenger seat. As with the rest of the R230-generation SL, a Mercedes-approved AKSE child seat can go there instead, seatbelt-mounted, with the airbag cut automatically once its transponder is recognized.
What looks like a rear bench is a parcel shelf — no child restraint is legal back there.
R230 SL owner-forum consensus (BenzWorld, MBWorld) on ISOFIX/AKSE fitment (owner-community sourced, not manufacturer documentation)
The long version
Values fell by more than half between 2008 and 2015 and have only partly recovered since, which is the used-SL trap in one chart: cheap enough to tempt a first-time exotic buyer, expensive enough in upkeep to remind them why the original owner sold. The supercharged V8 makes the case for buying it; the air suspension, folding hardtop and AMG service bills make the case against keeping it long. Involvement sits near the bottom because the driving experience was never really the point, comfort and a badge were, and no badges attach here because it does not distinguish itself even within its own bad-purchase category.