Yup, they were huge, heavy & complicated & they ran them to their limits when required - amazing engineering actually.
The big radial engines in fighters like the Thunderbolt & Sea Fury resulted in a fat front end, whereas the V12 types in the Spitfires & Mustang type fighters made for a much more slender profile.
The beauty of today's turbines is there is really just one big smoothly moving part instead of pistons, cams, valves, crankshafts, superchargers, etc, etc all trying to vibrate the whole mess apart. The trouble is, jets like to be at very high altitudes in thin air to make them efficient fuel consumption wise. That's probably why we don't have them in our normal land bound vehicles yet...