I tired those didn't find them very good.we use these
Natural Firelighters
Made using premium wood shavings and a thin coating of all-natural wax. Burn for 10 minutes. High heat output. Food safe. No unnatural odours. Free UK delivery. Over 15,000 positive reviews.www.lektowoodfuels.co.uk
I use these - one is always enough - very clean and no nasty smell - just light the little plastic wrapper it comes in.
Not cheap but no waste unlike the type you have to break off.