MG4 EV vs Leapmotor B05 UK (2026): Warranty, Range and Which to Buy

Ask any dealer and you'll get a confident answer about both brands. The reality is more nuanced. MG is not a plucky start-up — it is a badge owned by SAIC Motor (上汽集团), China's seventh-largest automaker, a Shanghai state-owned Fortune 500 giant with revenue of ¥299.59 billion in H1 2025 and a 14-year UK presence. The survival risk is about as low as it gets for a Chinese EV brand. Leapmotor is a very different proposition. The B05 is sold through Leapmotor International — a joint venture in which Stellantis holds a 51% controlling stake and owns the exclusive right to sell Leapmotor cars outside Greater China. Stellantis's direct involvement is a meaningful safety net: if Leapmotor itself faltered, the B05 product and dealer network would sit inside one of the world's largest automotive groups. But Stellantis posted a USD 26.3 billion net loss in 2025 — a fact buyers deserve to know, even if the strategic bet on LPMI is cited as a highlight. The warranty gap is the starkest expression of this confidence difference: MG backs the MG4 Gen 1 for seven years and 80,000 miles; Leapmotor backs the B05 for only four years and 60,000 miles. That alone could be the deciding factor for many buyers.

On price the two cars are essentially tied. The MG4 EV Gen 1 Long Range costs £29,995; the Leapmotor B05 costs £28,995 after Leapmotor's own £1,500 LEAP-GRANT discount (full list price: £30,495). Both trim levels are effectively one-spec affairs at this price point — you're not choosing between trim levels, you're choosing between cars. What you get for the money is genuinely different. The B05 arrives with more premium standard kit: frameless doors, lay-flat front seats, a 14.6-inch screen, 12-speaker audio and wireless CarPlay. The MG4 Gen 1 is simpler but has a comfort advantage for buyers who want a car they can live with for seven years without worrying. The MG4 also has V2L functionality — not confirmed on the MG4, while the B05's 3.3 kW V2L is standard and verified. On residuals, the MG4 carries CDL data showing MG brand averages around 35% at three years — not strong. For the B05, there is simply no data yet. The LEAP-GRANT caveat is real: the £1,500 saving is Leapmotor's own funding, not a government grant, and its post-September 2026 continuation is unconfirmed.

The headline numbers favour the Leapmotor: 300 miles WLTP versus the MG4 Gen 1 Long Range's 280 miles. But the real-world picture is more nuanced. Both cars use LFP chemistry, both are 400V architecture, and both sit in the same efficiency bracket. The B05's bigger battery (67.1 kWh usable versus the MG4's 62 kWh) accounts for most of the WLTP advantage. Where the B05 wins more clearly is charging speed: 174 kW peak DC versus the MG4's 150 kW. On a 30–80% rapid charge the B05 is quicker. If you regularly use motorway services, that matters. On AC charging, both offer 11 kW as standard — there's no difference here. The MG4's strength is in range, not charging: step up to the Extended Range variant (£32,995) and you get 338 miles WLTP on a 74 kWh NMC pack with 150 kW DC. That configuration outranges the B05 by 38 miles — but it also costs £4,000 more and switches battery chemistry, which complicates any direct comparison.

The China owner data is where Cathay EV earns its keep, because UK media simply cannot read this. The MG4's autohome score of 4.49 out of 5 from 1,514 reviews is genuinely good — better than most Chinese EVs. The praise is consistent: strong acceleration, rear space, stability. The complaints are equally consistent: tyre noise, wind noise, interior materials. The bigger concern, however, is the 车质网 satisfaction score of just 2.3 out of 5. Dig into that number and it is almost entirely service complaints — 1,219 out of 1,420 total — covering deposit disputes, delivery failures and dealer communication. Only 201 relate to product quality, and the top mechanical complaint (steering rack noise, 52 reports) is trivial by comparison. MG's dead-last ranking in UK Driver Power surveys for two consecutive years tells the same story: it's the brand experience, not the hardware, that drives the dissatisfaction. The Leapmotor B05 is too new to have meaningful failure data — its autohome score of 4.55 out of 5 comes from just 125 reviews (July 2026), and is the highest in its competitive set. China press reviews flag one specific issue that UK buyers also need to know: the Lane Keep Assist on pre-production cars was persistently active and extremely difficult to disable. Leapmotor has promised an OTA fix. Verify this is resolved at delivery before signing.

These two cars share a price tag and a powertrain layout. That's where the similarities end. The MG4 Gen 1 Long Range is a proven product from an established UK brand with seven years of warranty coverage, two independent NCAP 5-star ratings, and 14 years of UK dealer history behind it. Its weaknesses are also well-documented: dead last in UK Driver Power, a 2.3/5 Chinese service satisfaction score, and infotainment that does not match the Leapmotor's premium feel. But if you're buying a car you plan to keep for five years or more, the MG4's warranty is a compelling insurance policy — particularly because the Chinese owner data suggests the core engineering is sounder than the brand's UK reputation implies.

The Leapmotor B05 is genuinely exciting hardware. A 174 kW charger, 300-mile WLTP range, lay-flat seats, a 14.6-inch screen and V2L at £28,995 — no other car at this price offers that combination. But it is very new to market, unchecked by Euro NCAP, backed by a four-year warranty, and carrying an LKA issue that reviewers unanimously flagged as a pre-delivery problem. The LEAP-GRANT saving of £1,500 expires 30 September 2026 with no confirmed extension. Leapmotor's own survival is secured through Stellantis's majority stake — but Stellantis itself posted a USD 26.3 billion loss in 2025, and LPMI is a new entity.

Our read: buy the MG4 if you want the lower-risk path — seven-year cover, proven in the UK, decent engineering beneath a weak service reputation. Buy the B05 if you want the better kit for your money and are willing to accept the unknowns of an unproven new entrant — and you're buying before the LEAP-GRANT runs out.