CQRS "complexities" compared to "regular" apps

EntityWrongASsignment.php

<?php
class User
{
    private $email;
    private $emailChangedAt;
    public function changeEmail($email)
    {
        // assignment in wrong method, easy to miss in larger methods
        $this->emailChangedAt = new \DateTime("now");
        $this->apply(new EmailChanged(array("email" => $email)));
    }

    protected function applyEmailChanged($event)
    {
        $this->email = $event->email;
    }
}

History_vs_RealTests.php

<?php
class UserTest extends PHPUnit_Framework_TestCase
{
    /**
     * For every event a test of this kind is necessary,
     * where you compare all properties of the aggregate root
     * and all its children to a "real" object and one object
     * that was completly reconstructed from events.
     */
    public function testApplyChangeEmail()
    {
        $user = new User();
        $user->changeEmail("kontakt@beberlei.de");

        $userEs = new User();
        $userEs->loadFromHistory(array(
            new EmailChanged(array("email" => "kontakt@beberlei.de"))
        ));

        $this->assertEquals($user, $userEs);
    }
}

WrongApplyUsage.php

<?php
class Subscription
{
    private $position;
    private $user;
    private $valid;

    public function __construct(User $user, OrderPosition $position)
    {
        $this->apply(new SubscriptionCreated(array(
            "user"     => $user,
            "position" => $position
        )));
    }

    protected function applySubscriptionCreated($event)
    {
        $this->user     = $event->user;
        $this->position = $event->position;
        // now replaying this method requires "position"
        // to be the instance of the "position" at the point ´
        // where the event was triggered, otherwise it could be
        // "true" in the past, and "false" during reconstruction
        // of OrderPosition entity.
        $this->valid    = $event->position->isValid();
    }
}