There is a science to the use of the names of God (Allah) in Arabic. It is one of the spiritual subtleties of the science of remembering our Reality. Although the true gnostic (realized knower of Divine Reality) knows what s/he is referring to with the mention of the word 'God', there is not yet in the English language a science to bring that realization fully home to the unaware seeker. One of the true bases of sufi practice is exactly this science.
Compare simply the effect of repeating the word 'God' over and over again to the effects of repeating the name 'Al-lah'. Sufficient repitition causes one to think about and hopefully know, what one is saying. It also has the effect of knocking at a door until it is opened. This effectiveness of repitition holds true for all of the Arabic Names of the attributes of the Divine Reality and is another manifestation of the science of Gnosis (awareness). If we were to discover that one practice 'works' and the other doesn't, or that one method is manifestly more 'effective' than the other, what we would be comparing is the awareness received.
In English these Divine Attributes are objective descriptions, i.e. nouns and adjectives, and truly meaningful only to the gnostic who has already attained an inner realization of True Meaning. There is of course some benefit from the contemplation of the meanings of these words, but there is no real established science for total realization using only the English language. There is, however, such a science in Arabic, and this is the science of Dhikr (remembrance) as revealed by the prophet Muhammad and taught by the sufi masters.
It is said that when man remembers God, God remembers him. It is from this remembering by God of man that he knows his True Reality, and it is this true reality that constitutes the basis for true self-knowledge.
The journey to and through the self can be long and arduous. Without proper orientation, guidance, tools, and knowledge of how to use them, it is impossible. But that it IS possible at all comes as good news to man, for no effort is too much in the quest for escape from darkness and the plentiful reward of light and guidance from the Divine.
It is helpful for us to think of the journey in terms of stages of awareness. For the traveling through these stations we have the teaching of the Sufi Masters. It is not recommended to attempt this journey without a guide, and the teachings of the guide of this age can be obtained from any of his students.
It is said that to attain a moment of PURE contemplation is WORTH a life time of worship! To know Objective Reality we must have a sign (ayat) to contemplate, a Truth by which we may be guided. For the Sufis and Muslims alike, this Objective Reality, and the path to it, is indicated by the "Kalimah Tayyibah" ( Finest Words).