Thats excellent advice. There are certain things which its worth doing right, and spending a reasonable amount. Boots, Sleeping bag, pack and jacket are all things which have to work, because if they let you down, your going to have a miserable time.
That doesn't mean you have to spend a fortune, but the difference between a £60 sleeping bag and £160 sleeping bag can really count. I always advise people to get the Cotswold catalogue, because its free with an Explorer Card (always handy anyway) and you can sit down with a coffee and actually look at what a bag weighs, what its fill is, how it packs down, how warm it might be , and of course how much it costs (and that goes fro other kit). You don't have to ever buy anything from them, but it does make it a lot easier to see what the market is like. And then get the best you can for your money - good kit is worth it.