While it's certainly a big factor in a purchasing decision, I'm looking at the Starter Set for what it should accomplish: teaching someone not only to play D&D, but to Dungeon Master at the basic level.
Inside the box set, you get a 32 page Starter Set Rulebook, a 64 page campaign called Lost Mine of Phandelver, a set of polyhedral dice, and five pregens to run the campaign.
The Starter Set Rulebook is the player's introduction to roleplaying, and it does a rather pedestrian job explaining things. Out of the six introductory pages of Chapter 1, a page and a half is dedicated to this, while the remainder of the chapter meanders through ability scores, skill checks, and saving throws.
Chapter 2: Combat starts out strong, but quickly falls into a mish mash of rules for special situations. I assume this is fewer than in the 5e PHB, but to quickly look up a rule was easier in the free pdf of the rules that wizard provided.
Chapter 3: Adventuring covers jumps, rest, a paragraph on experience points through level 5, and equipment.lists.
Chapter 4: Spellcasting is massive in this small book. Basic spells rules are covered followed by nine pages of spells, sorted not by class, but in straight alphabetic order.
Lost Mine is a nice campaign, introducing a number of different setting to adventure in, as well as setting up at least the barest of role playing opportunities. I did find that you should get at least five of your friends together, as the adventure focuses on the essential trait of balance towards the encounters. When I introduced my girls to Dungeons & Ponies, the final encounter we played required double characters and me running an NPC, and while there may be talk as to how to adjust the encounter level for weaker groups, it's not mentioned often.
The polyhedral dice were nice, but horribly unbalanced. My one daughter rolled a 3 on exactly half her rolls, and her younger sister added a few more.
What I'm most concerned about the lack of editing. Whether the most practical approach was eschewed for page space is irrelevant. There is something wrong when you provide a basic stat line for the encounter. I'm not talking about the stat blocks from 3E, which included blood type and favorite IKEA purchase. I mean a basic line that includes Armor Class, Hit Points, basic penalties and bonuses. Special abilities can be noted on the line, with advise to refer to the monster section in the back of the book. If I didn't memorize the AC of a goblin after three sessions, I doubt a 12 year is going to while he DMs his first game.
I'm wholly disappointed with this product. Although the nostalgic version of me from my Mentzer Red Box would have killed for a campaign like Lost Mine to start with, so many things are disorganized and haphazard that I can only give the D&D Starter Set Two out of Five gnomes.
Truth be told the free D&D 5E pdf "sampler" is a far better tool for anyone with any experience with RPGs.