THEME - Theme is the first thing to like or dislike.

ARTWORK - Artwork is the 2nd thing to like or dislike.

PLAYFIELD LAYOUT - Playfield layout seperated into 2 different categories.
a) can u see alot of the playfield and its various shots or is alot of it hidden which is no good for play or cleaning/maintainence
b) are the shots challenging and varied, will it be a game which flows and has speed, or is it a stop start sort of playfield

AUDIO - Is the audio really annoying, or is it varied and interesting, something u can listen to over n over again, do u like the audio ?

GAME OBJECTIVE - what is the overall objective of the game, what challenges are the main attractions, are there special toys to lock balls, unusual ramps, timers for different missions, what do u continually have to do to have fun playing this game

GAME UNIQUENESS - if u have ALOT other pinball machines, what is different about this title, what makes it stand out from others in a large collection.
Is it a machine you are buying just for yourself to play, or is it a title u are also buying to share with as many friends n family as u can.

Some people rate a game after 5 plays, some people play 50 games, some people just buy it anyway and learn about the game over a 3 or 4 month period once they get it home.
The one thing I have learnt about my DMD machines, is that there are things, fun things u find out about a machine sometimes after having a few hundred games, so to rate a machine after 5 plays to me is just a guess, because you cannot learn a machine to its capacity unless you have put alot of time into it. 5 or 10 plays wouldnt even scratch the surface of the various programming that the machine has.
  Many missions/modes would not even have been played, so rating a game after 5 or 10 plays would be rating only part of the game.

You can rate it quickly, first impressions etc, but to permanently rate a game after 10 minutes would just be guessing in my book.
That would be a 10 minute rating, not a decent evaluation based on lengthy game time and game experience.  I say this because if u then played the game for another 3 or 4 hours, you would have learnt alot more and experienced alot more than a 10 minute quick rating.
(like judging a woman 4 ever after a 10 minute date versus being married to her for a while.lol   yes, its very different.lol)

I have always said there is no such thing as a bad pinball machine, because just because one person hates it, doesnt mean the next person doesnt love it.