In the UK if you direct a foreign company but are UK based then HMRC will consider it a UK company for tax purposes.
I looked at incorporating in Ireland because A. We wanted good Euro banking which the UK doesn't have and B. The corporate tax rate is a mere 12.5%.
The EU flexibility rather concerns other aspects. For example in Germany if you wanted to have a limited liability company (GmbH), you needed to have 20,000€ capital. The british limited had a lower requirement so lots of small german businesses incorporated as a Ltd. Now there is a new limited liability company in Germany called the "UG" without the minimum capital, which otherwise would never have happend or at least not as fast.