Where each one leads
Mercedes-Benz SLK
- On Canada's official test the most frugal 2016 Mercedes-Benz SLK uses 8.5 l/100 km, the 2019 Porsche Cayman 9.4.
- New Mercedes-Benz SLK cars registered in Europe in 2020 average 153 g/km of CO₂ on the WLTP test, against 192 for the Porsche Cayman in 2022.
Porsche Cayman
- Against cars of the same age, the Porsche Cayman comes out better at its first MOT test (passes 27% more often than average) than the Mercedes-Benz SLK (passes 16% more often than average).
- Fewer Porsche Cayman cars in the Netherlands carry an illogical odometer record (6.1% against 9.5%).
Only measures that do not depend on how many cars were sold: pass and failure rates against cars of the same age, ratings, fuel use and CO₂. How we compare
At a glance
| Mercedes-Benz SLK | Porsche Cayman | |
|---|---|---|
| Model years in the US safety record | 1998–2012 | 2005–2020 |
| New cars registered in Europe | 75,551 (2010–2020) | 4,921 (2010–2022) |
| Licensed in the United Kingdom | 47,128 | 8,584 |
| On the road in the Netherlands | 9,739 | 815 |
| In traffic in Finland | 2,181 | — |
EEA new-car registrations (CC BY 4.0) · DVLA licensed vehicles (OGL v3.0) · RDW (CC0) · Traficom (CC BY 4.0) · generations: Wikidata (CC0).
Reliability and problems
| Mercedes-Benz SLK | Porsche Cayman | |
|---|---|---|
| UK MOT first-time pass rate | 73% | 89% |
| … against cars of the same age | +16% | +27% |
| New York safety inspections failed | — | 0.4% |
| … against cars of the same year | — | −82% |
| Illogical odometer records (NL) | 9.5% | 6.1% |
| US owner complaints | 74 | 29 |
| Most complaints about | Visibility | Power train |
| Model year with most complaints | 2002 (25) | 2014 (7) |
| US recall campaigns | 3 | 5 |
| Manufacturer service bulletins | 79 | 2,688 |
| NHTSA defect investigations | 9 | — |
Complaint, recall and bulletin counts grow with the number of cars sold and are not adjusted for it. UK MOT: DVSA anonymised MOT results (OGL v3.0); New York: DMV inspections; complaints, recalls, bulletins and investigations: NHTSA (public domain); odometer: RDW (CC0).
Fuel, emissions and price
| Mercedes-Benz SLK | Porsche Cayman | |
|---|---|---|
| Official combined fuel use, Canada | 8.5 l/100 km (2016) | 9.4 l/100 km (2019) |
| Official CO₂ of new cars in Europe | 153 g/km | 192 g/km |
| Average power of new cars in Europe | 120 kW (161 hp) | 213 kW (285 hp) |
| Average mass in running order | 1,578 kg | 1,434 kg |
| Dutch list price when new (median) | €61,479 | €95,210 |
| Average odometer in Finland | 175,000 km | — |
Canada: NRCan Fuel Consumption Ratings, most frugal version of the latest year (OGL Canada). Europe: EEA monitoring of new-car CO₂ and on-board fuel meters (OBFCM), CC BY 4.0. Price: RDW catalogue price (CC0). Finland: Traficom (CC BY 4.0).