According to the calculator yes, at £1800 a month, saving, with 7% return you'll save up £312k in 10 years.
But, if you have children, that changes things such as child care or one of you decides to stay home losing one income, or you want to move for better schools or to be near family etc...
In your position I'd feel a lot better with a paid off home or a really good emergency fund when I retire, in addition to the invested funds, to weather a major emergency or market downturn.
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