Lenovo's premium, business-focused ThinkPad X1 range continues to expand. Designed to marry high-spec functionality with great design, X1 laptops can be expensive -- the last ThinkPad X1 I reviewed, the ThinkPad X1 Nano, has a starting price of £1,739.99 (inc. VAT), or $1,487.40 in the US. This is closely matched by the convertible ThinkPad X1 Titanium Yoga, reviewed here, which starts at £1,669.99 in the UK, or $1,474.50 in the US.