The game is intended for players and GMs who haven't played rolegames, and begins with a one-page summary of the rules (which is also a short episode). There's also a blow-by-blow writeup of an adventure, which shows the players ignoring the GM's plan, a nice touch. The rules themselves are simple. Players divide 7 points between two stats, Brawn and Presence. They then get 9 skill points, to divide among six different skills picked from a list of 14. Knights (the only character allowed in the basic game) must put points into Arms and Riding.
The game system consists of throwing as many coins as your Brawn or Presence, depending on the situation. If you throw at least one head, you succeed. Some tasks are more difficult -- the GM might require 3 heads. Often a skill is involved, and you'll add the skill value to the number of coins to throw. If you're competing with a foe, whoever throws more heads wins.
Combat is an extended resolution. Both contestants add Brawn and Arms, and modifiers for weapon and armor. The person who throws the fewest heads removes the difference from his next throw.
The system was easy to explain (at least to gamers), and plays fast. As the book warns, multiple-person combats can take a while.
The object of the game is Fame, which is like experience points, but awarded subjectively by the GM. Every 1000 Fame points (about 5 adventures) earns a character a new skill point.
My players felt a bit constrained by having to play chivalrous knights, but luckily the Advanced Game allows characters other than knights -- even female adventurers -- and provides 15 new skills. There are also personality traits like Afraid of Rats, Cruel, Gossipy, Squandering, or Truthful. If the GM is impressed or amused by in-character use of a trait, he can award Fame.
The Advanced Game also introduces the concept of assistant story tellers (GMs), who can take over for a scene. In our playing group, another GM took over the story line for an episode or two. I've seen this happen before, but Prince Valiant encouraged it.
I think the game will serve its target audience well -- the rules are simple enough to be learned quickly, and don't get in the way of the story. They should also be accessible -- they're well written, with examples, and often illustrated by panels from the comic. Best of all are the how-to sections which explain how to be a player or GM, and 20 short episodes to get started with.
After seeing the gorgeous illustrations, I decided to get the reprints of the comic strip. To my surprise, Chaosium did a better reproduction job than at least two different reprint series. It was nice to see the art in its original context, however.
My players and I had some problems with the Prince Valiant background -- we'd have preferred the more historical background from Chaosium's Pendragon. A more detailed map would have been nice, too.
The game tells the GM not to worry about money, but in several places talks about expensive armor or horses.
I recommend Prince Valiant. You may not want to run a Valiant campaign, but it should be just the thing for a quick bit of roleplaying between your serious games.