Adizero Boston 12 vs Endorphin Speed 4

The Boston 12 is where adidas fixed the Boston. Versions 10 and 11 had a reputation for a hard, brick-like midsole, and reviewers mostly agreed this one rides softer and livelier while keeping the snap that makes it a tempo running shoe. On paper it's 267g with a 7mm drop and fibreglass rods rather than a carbon plate, so think of it as a training partner for faster sessions and marathon-block long runs, though one reviewer reckoned it could double as a budget racer. Women's Running UK gave it four stars, and Runnea's reviewer picked out how stable it stays on long runs. Where it falls down is fit: a thin tongue, laces that slip and a soft heel counter that heel strikers may not trust. Adidas has since released the Boston 13, which keeps a similar ride and pads the heel and tongue. So the 12 makes most sense when it's clearly the cheaper of the two.

The Saucony Endorphin Speed 4 is the do-everything plated trainer, and one of the most complete running shoes in its class. At 233g with an 8mm drop it sits in the sweet spot between a cushioned daily trainer and a stripped-back race shoe, so one pair covers your tempo days, your long runs and the odd parkrun. The plate gives you a gentle nudge through toe-off without the aggressive, all-or-nothing feel of a full carbon racer, which is exactly why so many runners keep coming back to it. We rate it as the shoe to reach for when you want speed without committing to a dedicated marathon shoe. It is not the cheapest tempo option at RRP, and the plusher Endorphin Speed 5 has since taken over the line, but the Speed 4 remains a brilliant buy when it drops in price. If you want the plate but not the price, this is the one to watch.