This is a foundational text in understanding the French Arthurian tradition. If you are studying medieval literature and can't read Chretien de Troyes in his original, then this should be high on your reading list.
On the other hand, if you are a casual reader interested in getting to the sources of the King Arthur stories, you may find Chretien rather disappointing.
For modern tastes, there is far too much narrative here and not enough characterisation or description. Chretien also has the habit of interrupting his denouements with apparently irrelevant observations on the nature of courtly love.
Clearly, Chretien's audience had very different expectations from most modern readers. If you want to enjoy the Arthurian Romances, it's worth trying to get into the mind of the original readers.
You need to remember that although today we see Arthur as escapist legend, in Chretien's time the 'matter of Britain' was a legitimate subject for an intellectual engaging other intellectuals.
Equally, looking back through the eyes of Tennyson (if not Hollywood), we tend to see Arthur as a romantic ideal. This assessment is further clouded by the title of this translation. The word 'Romance' here really means 'Novel', rather than something concerned with romantic love. The idea of love in Chretien is the idea set out in Andreas Capellanus 'the Art of Courtly Love', not that of 'Idylls of the King'.
Finally, the complex of social castes in Chretien was not something exotic or ancient to the original readers. There are layers of meaning which would have be obvious to his audience but which are concealed from us.
I would recommend the chapter in Erich Auerbach's 'Mimesis' entitled 'The Knight Sets Forth', which discusses Chretien's 'Yvain' as the best general introduction to this collection.