Depends what you mean by 'serious downside'. In the worst case scenario of no deal, would an average tariff of 5.2% have a greater effect than the 30% decline in the value of sterling 10 years ago, or the 12% decline in sterling since 2016? And, before you answer, remember that nobody is expecting a worst case scenario. In fact, variations of 5.2% are typically faced by exporters all the time, due to currency fluctuations. It is why larger firms hedge against them. Not something to be welcomed, but neither something to be described in hyper-inflated talk of cliff edges and catastrophes. It is the language of the snowflake generation who like to portray themselves as "heartbroken" if they miss a bus, or "devastated" if they catch a cold.