Like the previous reviewer, I too found this collection of sagas most valuable for its unique primer on ancient Icelandic law, culture and customs. The Saga of Gisli and the Saga of Hord were especially useful in this regard. Unfortunately, if you're looking for developed characters or a compelling story that is easy to follow, you'll have to look elsewhere.
Thankfully, the Saga of Grettir not only adds to the history lesson by contributes the story of a character full of condradictions and one who changes over time as a result of his experiences--many of which involve hacking other people to pieces in bloody combat. Battles with supernatural demons, over rights to beached, dead whales and on top of beached dead whales will enhance (for most readers) a sense of alien, almost unimaginable experiences. The Saga of Grettir have been compared to the Illiad but I didn't think there were enough developed characters or central theme to make that a valid comparison. Grettir has considerably more characters and character development then Beowulf, but the parallels of dialogue and emphasis on bloodshed and gore make the two tales comparable. Perhaps bloodshed is also what Grettir, Beowulf and the Illiad also have most in common.
The translator's introduction, foot notes, maps, geneological graphs and appendices of place names and obscure references were all helpful in aiding my understanding of the Sagas. Unfortunately however, the translation of text is what counts more than anything. While this one was adequate, it was full of akward phrasings and far, far too many colloquialisms derived from modern British slang and vernacular to qualify as a superior translation. Sometimes modern speech can aid our comprehension of ancient stories but in this collection it was a distraction that diminished the mood, tone, and quite frankly even the coherance of these austere works.
If that sounds elitist I'm sorry but that was just my overall impression. I hasten to add that I do not read Icelandic nor have I read other translations of these works. These are interesting stories and the translator did the best he could. Its worth it to read every page from end to end including the informative introduction and appendices.