WARNING: I am quite possibly the world's biggest Inquisitor nerd. The following post may contain opinions.
It is possible to play Inquisitor as what is effectively a
PvE game, but its strength is really as a
PvP mix of roleplay and skirmish.
The best way I can describe it is "Tabletop improv theatre" - the players are the actors, the characters are their roles and the
GM is the director/scene setter. "Winning" is only indirectly the point; victory is what the characters (probably) want, not what the players are trying to achieve; their goal is the enjoyment of... well, acting the parts and partaking in some thrilling heroics.
Most
RPG or
RPG-like games are not built with
PvP play in mind - they use hit points or some other damage system that really just means that a fight is about who runs out of hit points first. Inquisitor's progressive debilitation is what makes it suitable for having player characters fight player characters.
Unfortunately, the approach for the game was only really described in the designers' notes... which were right at the back of the rulebook (and were often never read!) and never made it into the downloads. D'oh.
Now it may initially seem that the
GM, at least in scenarios with no
NPCs, doesn't have a heavy role, but playing the
NPCs isn't the only part of a
GM's role. Primarily, they scene set and adjudicate rules, the latter of which is particularly important with the
PvP nature of the game; that character that they're shooting at isn't an
NPC goblin, it's another player's creation, so imbalances that can be overlooked in a
PvE game - because all the players are (generally) a team and are thus normally benefited/penalised somewhat in kind by any rule - become more major points of contention.
And, to be honest, many of my favourite Inquisitor games have been ones I GMed. This is the one that got me voted "Best
GM" by the other players at an event at WHW earlier this year:
Hotlinking may be broken (what's the gorram point in Flickr giving me BBCode tags to use if it doesn't let them work), but
this should at least link to a bigger image.
I didn't have much actual part as far as "acting", but my role was still important... and enjoyable. The film and theatre industry would be pretty sunk if people couldn't enjoy watching a story. Sure, there's less appeal in watching a
PvE game you've written (as it usually goes approximately as the
GM anticipates - i.e. the bad guys all get killed), but writing for a
PvP game... you really don't know what's going to happen.
~~~~~
On another note, that picture actually allows me to bring up a counter point to something chromedog said. Aside from the fact that the
GW team had actually deliberately produced this terrain with a MkI Rhino embedded in it (visible in the top right of the image), pretty much everything here was sized just fine for 54mm. (Even the Rhino could fit under the bridges between buildings).
28mm buildings have to be made to deal with big models like Terminators with back banners, or other similar models like Mega Nobz, Tau Battlesuits and now, Centurions. Natural things like trees and rocks look much the same whether they're big or small.
I'm not saying anyone has to play 54mm (I happily play both 28mm and 54mm), but the idea that it needs a separate terrain collection is largely untrue. With only marginally clever design (and not covering everything in dead bodies), most terrain pieces can comfortably do double duty.
~~~~~
As far as the transition between 28mm and 54mm, it's pretty much the same. Use half inches or centimetres as the "yard" the game talks about.
The only warning I have is that the ease of grabbing a Space Marine Librarian or a Terminator armoured Inquisitor from their
40k army means that players who just don't get the point of the game have an easier time of ruining a 28mm scale game for other people if the
GM doesn't clamp down hard on such things. There are so many people who treat the game sensibly, but it only takes one person to ruin it...
The thing is, Inquisitor is not set on the front lines of the 41st millennium so, while things like Space Marines do appear in the rulebook, they should mostly be off performing surgical strikes somewhere far distant until such a point as an Inquisitor actually requires their services (hint: seven foot tall super soldiers in bright blue power armour do not incognito investigators make).
Similarly, a lot of the heavy equipment we're used to seeing on
40k models is ill-suited for many investigations. "Even" a bolt weapon is going to catch unwanted attention, be an unpleasantly heavy weight (who really wants to carry that brick every second of an investigation) and a struggle to find ammo for away from proper supply lines.
Also, these are characters. Their models should be individual and distinct, to best represent the unique protagonists (or antagonists) they are.
As such, players need to ignore any urges they might have to pick just any old models from their
40k armies. Inquisitor models, big or small, should have the effort put in to make them unique and appropriate for the nature of the Inquisitor game (both in and out of character) - this extra effort isn't really a titanic task when you only have a few models to do!
~~~~~
As an overall guide to Inquisitor, I would strongly recommend throwing the random generators (and
definitely the ready reckoner) out.
Collaborative experience has shown the frequently high stats that they give are not a particularly fulfilling way of playing the game, as regularly getting hit chances like 92% take the uncertainty out of the game and effectively just reduce conflicts to whose action dice say they get to shoot first.
This is a good overall guide to player tested thoughts on character creation.
Beyond that, keep the pace going (don't have too many models on the table at once!) and encourage thrilling heroics but, above all, make sure everyone's having fun.