How to remove buttons from CKeditor 4

I finaly found how, but I don't like this way as instead of removing what you don't want, you define which buttons you want (and simply don't put what you don't want). When you call CKeditor.replace you can define the toolbar like so:

    CKEDITOR.replace( 'YOURE_TEXT_AREA_ID', {
    toolbar: [
    { name: 'document', groups: [ 'mode', 'document', 'doctools' ], items: [ 'Source', '-', 'Save', 'NewPage', 'Preview', 'Print', '-', 'Templates' ] },
    { name: 'clipboard', groups: [ 'clipboard', 'undo' ], items: [ 'Cut', 'Copy', 'Paste', 'PasteText', 'PasteFromWord', '-', 'Undo', 'Redo' ] },
    { name: 'editing', groups: [ 'find', 'selection', 'spellchecker' ], items: [ 'Find', 'Replace', '-', 'SelectAll', '-', 'Scayt' ] },
    { name: 'forms', items: [ 'Form', 'Checkbox', 'Radio', 'TextField', 'Textarea', 'Select', 'Button', 'ImageButton', 'HiddenField' ] },
    '/',
    { name: 'basicstyles', groups: [ 'basicstyles', 'cleanup' ], items: [ 'Bold', 'Italic', 'Underline', 'Strike', 'Subscript', 'Superscript', '-', 'RemoveFormat' ] },
    { name: 'paragraph', groups: [ 'list', 'indent', 'blocks', 'align', 'bidi' ], items: [ 'NumberedList', 'BulletedList', '-', 'Outdent', 'Indent', '-', 'Blockquote', 'CreateDiv', '-', 'JustifyLeft', 'JustifyCenter', 'JustifyRight', 'JustifyBlock', '-', 'BidiLtr', 'BidiRtl', 'Language' ] },
    { name: 'links', items: [ 'Link', 'Unlink', 'Anchor' ] },
    { name: 'insert', items: [ 'Image', 'Flash', 'Table', 'HorizontalRule', 'Smiley', 'SpecialChar', 'PageBreak', 'Iframe' ] },
    '/',
    { name: 'styles', items: [ 'Styles', 'Format', 'Font', 'FontSize' ] },
    { name: 'colors', items: [ 'TextColor', 'BGColor' ] },
    { name: 'tools', items: [ 'Maximize', 'ShowBlocks' ] },
    { name: 'others', items: [ '-' ] },
    { name: 'about', items: [ 'About' ] }
]
});

(For reference this is the standard full toolbar) Items represent buttons so simply delete the items you don't want. Thats it.

Is there any better answer ?

Based on reinmar answer and tested here is the better answer. Add this in your ckeditor config.js :

config.removeButtons = 'Underline,JustifyCenter';

For reference you can find the complete list of CKeditor 4 buttons there : http://ckeditor.com/comment/123266#comment-123266