The right choice depends on how many EU member states you actually need protection in and what your budget allows.
An EU trademark is more expensive than a single national registration, but it covers all 27 member states through one application and one renewal. If you need protection in three or more EU countries, the EU trademark is typically the more cost-efficient option. If you only operate in one or two specific member states, national registrations in those countries are cheaper.
There is also a risk consideration: an EU trademark is unitary. A successful opposition by a national mark holder in any one member state can block the entire EU application. A national trademark in one country is not vulnerable to opposition from mark holders in other member states. For this reason, some businesses register both a national trademark in their primary market and an EU trademark for broader coverage.