MG 9: which version to buy — AT 340 hp vs AT 544 hp
The MG 9 has one generation (from 2024-02-01, still in production) and one body: Liftback. The buying choice is not between generations. It is between two versions that share the same catalogue name AT. Name them by power so they do not collide: AT at 340 hp and AT at 544 hp. Both are Electro, both use Automatic with 1 speed, both list CO2 0.
The MG 9 has one generation (from 2024-02-01, still in production) and one body: Liftback. The buying choice is not between generations. It is between two versions that share the same catalogue name AT. Name them by power so they do not collide: AT at 340 hp and AT at 544 hp. Both are Electro, both use Automatic with 1 speed, both list CO2 0. The split is power, drive, torque (measured on one side only), and 0–100 time.
Specs: the two AT versions side by side
| Version | hp | kW | Nm | Displacement | Fuel | Cylinders | Layout | Boost | Gearbox | Speeds | Drive |
|---|---|---|---|---|---|---|---|---|---|---|---|
| AT (340 hp) | 340 | 250 | not measured | not measured | Electro | not measured | not measured | not measured | Automatic | 1 | RWD |
| AT (544 hp) | 544 | 400 | 713 | not measured | Electro | not measured | not measured | not measured | Automatic | 1 | AWD |
Displacement is not measured on either AT, so power per litre cannot be calculated. Cylinders, cylinder layout, and boost are not measured on either AT; do not fill those cells from other MG models.
What the extra 204 hp actually buys
544 − 340 = 204 hp. 400 − 250 = 150 kW. Ratio: 544 / 340 = 1.60, and 400 / 250 = 1.60. The stronger AT is 60% more powerful on both horsepower and kilowatts.
0–100: AT 340 hp is 5.7 s; AT 544 hp is 3.7 s. Difference: 2.0 s. Ratio: 5.7 / 3.7 ≈ 1.54 — the 340 hp AT takes about 54% longer to reach 100. Top speed is not measured on either version.
Torque: AT 544 hp lists 713 Nm; AT 340 hp torque is not measured. You cannot claim a newton-metre gap. You can only say the 544 hp AT is the version where peak torque is in the data.
Drive: AT 340 hp is RWD; AT 544 hp is AWD. That is the second hard split after power. Same Automatic, same 1 speed, same Electro fuel, same CO2 0. If you need AWD, the data leave only the 544 hp AT. If you need RWD, the data leave only the 340 hp AT. There is no third AT that mixes 340 hp with AWD or 544 hp with RWD.
Generations: nothing later to wait for in this catalogue
1 generation, start 2024-02-01, stop not measured (still current). Body: Liftback. Versions in this generation: 2, both named AT. There is no restyling row and no second generation in the data, so there is no “buy the facelift” or “wait for gen 2” comparison. Chassis items that are measured are identical on both AT rows: front suspension Independent, spring; rear Independent, spring; front brakes Ventilated disc; rear brakes Disc. Choosing the 544 hp AT does not change those measured chassis labels.
Performance and economy
| Version | 0–100 | Top speed | City | Highway | Combined | CO2 |
|---|---|---|---|---|---|---|
| AT (340 hp) | 5.7 s | not measured | not measured | not measured | not measured | 0 |
| AT (544 hp) | 3.7 s | not measured | not measured | not measured | not measured | 0 |
Fuel consumption (city, highway, combined) is not measured on either AT. Tank is not measured. MPG is not in the data. Economy comparison between the two AT versions is therefore not measured on consumption; the only shared measured emissions figure is CO2 0 on both.
Dimensions, weight, wheels
Kerb weight: not measured (both AT). Gross weight: not measured (both AT). Ground clearance: not measured (both AT). Tank: not measured (both AT). Wheel sizes: not measured (both AT).
Weight per horsepower cannot be calculated for either AT. You cannot use “lighter for the power” as a reason to pick one AT over the other. The measured difference that does exist is power, drive, 0–100, and (on the 544 hp AT only) 713 Nm.
Which version to choose
Choose AT at 340 hp / 250 kW, RWD, 5.7 s to 100 if you want the lower-power Electro Liftback in this generation. It is the only RWD AT in the data. Torque, displacement, top speed, consumption, tank, kerb weight, gross weight, ground clearance, and wheels are not measured on this version.
Choose AT at 544 hp / 400 kW, AWD, 713 Nm, 3.7 s to 100 if you want the higher-power Electro Liftback. Arithmetic vs the other AT: +204 hp, +150 kW, 1.60× power, −2.0 s on 0–100, and AWD instead of RWD. It is the only AWD AT and the only AT with a measured torque figure (713 Nm). Top speed, consumption, tank, and all mass/clearance/wheel figures are still not measured.
There is no price in the data, so “what the extra money buys” cannot be stated in currency. What the step from the 340 hp AT to the 544 hp AT buys in measured terms is 204 hp, 150 kW, AWD instead of RWD, a listed 713 Nm, and 2.0 s off 0–100, on the same generation, same Liftback, same Automatic 1-speed, same Electro, same CO2 0, same Independent, spring suspension front and rear, same Ventilated disc front and Disc rear brakes.
If the decision is generation, there is only 1 generation (from 2024-02-01). If the decision is body, there is only Liftback. If the decision is gearbox type, both AT versions are Automatic with 1 speed. The live fork is AT 340 hp RWD versus AT 544 hp AWD.