RPGA has the same spread of gamer types as homegames, EXCEPT: those who espouse "Who needs rules? Let's just inhale deeply of the toke of freeform gaming. I mean, what is D&D but a bunch of friends talking?" will be fed to the monsters in the first encounter
Format is key here. If the setting is not time-limited, then lengthening 4 hours of combat and quick NPC interrogation to 5 or 6 hours with full RP is a very enjoyable mix.
If the goal is to be done come heck or high water in 4 hours, then don't expect to get
any RP done besides character introductions and witty remarks.
Presuming this is Living Greyhawk we're talking about, and not the series of one-shots known as "D&D Classics" then you have to think of it this way:
"If I and my companions make no effort to RP, there will be none."
Living Greyhawk would have a completely different feel if the same group of six
characters always played together. In practice, most people can't arrange that, so
subgroups of 2-3 players play together most of the time, and the other 3-4
players are people you've not met or gamed with more than five times.
If Living Greyhawk had come out when I was in high school, me and my buddies would
have been a solid lock to play virtually every game together.
Now, I'm 30+, married, involved with my church, non-gaming friends etc. I can make
time to hit the occasional RPGA gameday, and I'm in a 1-2 times a month homegame,
and there's no way for the schedules of almost any six 30+ professionals to merge
very often.
If you're worried about how often you can RP and all that, then I would only
recommend playing RPGA events if you can get at least one other friend to always
play them with you, so you can team up to add more RP to the session.
One big disadvantage of the RPGA is that the same rules booklet that ensures most
judges run things by the rules also limits said judges.
The judge is running a published adventure, and has only minor powers to embellish
it. Even if you had a great in-character RP with some famous NPC in Part 1 of a
series, unless the same judge is your judge for part 2, said NPC won't remember
anything of the cool conversation you had.
After all that, on the bright side, for those of us with busy schedules, it means the
same PC can adventure from level 1 to 10+ with many different judges, enjoying
a potpourri of styles and players, even if the player can't be around consistently
on the 2nd saturday of every month, etc.
Realistically, presuming you can't get a regular group of good RP people who also
understand game mechanics to adventure with, you should seek out a group of
RPGA players (group = club = 20+ players) who are enthusiastic about bringing in
new players and going with the flow to make the game better.
I know of some RPGA judges who are truly "screen monkeys" as depicted in Knights of
the Dinner Table (comic strip and book) and ceaselessly talk during the game about
how parts of the module are poorly written, etc.
I know of some RPGA judges who I wouldn't mind being in a homegame with, who do
their best to accommodate the players, RP when the group wants it, monotone the
boxtext quickly to get to the next combat for the wargamers, and otherwise evaluate
each group of players to help them out.
Most groups will be a mix, with the boxtext read or paraphrased well and at a good
pace, with a DM who can think on the fly, improv RP well, and provide a good
challenge for the players.
You know how at a restaurant, if you say nothing, the meal comes to you as-is on
the menu, with mayo, mushrooms, onions, whatever, and if you want something
different, you have to ask for it?
Same here. If you need an RP-heavy group, you need to recruit it yourself. Freeform
gamers who change rules on a whim, for purely emotional non-logical reasons flee from
the RPGA in droves. They simply don't last in a structured environment.
RPGA is maybe 8 of 10 in structure compared to an average homegame of 5.5 where
the DM occasionally makes exceptions, but always thinks big decisions through, and
has some respect for the rules as written.
If you know the DM and other players, and trust them, then I've just written a few
hundred words for nothing. It's all about the people, not the system.