An Alpkit Pipedream 400 has been a staple in my sleeping bag collection for most of the last decade, so it’s been interesting to compare a brand-new bag with my old one. I think it’s a worthy ‘quiver killer’ of a bag. It doesn’t drip with unnecessary bells or whistles – it just quietly gets on with the job.

The chief ingredient is 750 fill power, RDS (responsible down sourced) down in a box wall baffle construction. A box wall build retains far more warmth than stitch-through, and the shorter horizontal baffles keep more of the down in place across the body. The zip is full length and 2 way – great for venting when things get stuffy – and the bag can be ordered with a zip on either left or right side. A full-length zip baffle prevents drafts, and the zip is chunky and runs smooth. The neck closure is on a simple, un-elasticated toggle, so it can be sealed around the face in chillier conditions, and a shaped neck baffle traps warm air inside. This simple setup works perfectly well.

The fit is described as a narrow, tapered ‘mummy’. For me, it’s a goldilocks width – not too narrow, not too wide. There’s plenty room to wiggle and stretch legs, hips and feet, but not enough for cold spots to develop. I am 5’8” and a medium build, but if I were even an inch or two taller, I’d choose the ‘Long’. Along with temperature, fit is very subjective, and note that the bag is ‘unisex’ – women, those taller or with a different build than I, will experience that fit and feel differently.

Pipedream and sleepy tester. Credit: Mick Mcgregor

On the warmth and sizing front, it worth pointing out that the ‘Long’ contains the same amount of down as the ‘Regular’, so it will be cooler – by a couple of degrees, say Alpkit. For me, the Pipedream 400 is a pretty true 3 season bag, in a world where temperature ratings are not standardized and need to be taken with a hefty dose of salt. I’ve used my original in early March with complete snow cover at 1100ms in the Cairngorms (cold and dry, ‘alpine’ conditions), into high summer in wet’n’windy Wales, on Arctic circle packrafting expeditions and well into November back in stormy Scotland. Admittedly, in that first example I was chilly, but nighttime temperatures were right at its ‘limit’, and I still got some rest.

It compresses to the size of a medium loaf in a drybag, and its packed weight is modest enough too. I love that it’s not wildly expensive, so I’m not precious about using and occasionally abusing it. My only reservation is that the proprietary hydrophobic down treatment on my original didn’t prove quite as effective as some others. The hood suffered from damp, with the down losing volume and moving within the slightly larger baffles there. The shell was a little prone to wetting out from condensation, making the down less efficient. This old bag was much revived with a careful wash and reproof, and performance far improved since.

It remains to be seen how the new version will perform longer term, but I have bags half as old and twice as expensive that are in worse nick than my original Pipedream. Otherwise, it’s a very affordable and genuinely 3 season rated sleeping bag. The new version is around 70g lighter than my previous one, too.

How David tested

David Lintern took on a new Pipedream 400 for the tail end of winter 25/6, used in a damp bothy and over a few wild camps. He is 5’8”, sleeps cool but not cold and was able to compare it to an older model. See how it measures up to others on the market in our guide to the best sleeping bags.

This review was first published in our wild camping kit special issue.