Sorry for the old thread revive but when this thread started I didn't own either....now I own both (ST Pro & IMVE). Also a buddy of mine has Met Pro and I've spent a fair amount of time on it as well.

Honestly I don't think you can really go wrong here. I think they are all great games. Gun to my head I would go IM>ST>Met. But I could certainly see arguments for any order (personal preferences).

I like fast difficult games and IM is the king of that hill. It really is pure adrenaline and it really does "fight back".......love it. That being said it is also the newest to me and that can still be weighing in on my order of preference.

ST - much deeper and great flow. Even though it got a code update since this thread started.....it still needs another one to bring out it's full potential.

Both ST and IM have great sound and great light shows.....shaker motor highly recommended for both.

The secret to IM is setting it up correctly. Little things like setting the Monger start to "hard" and disabling the back post can make a very big difference in how it plays.

With ST it's all in how you play it. There are so many ways to attack it and you really should have a plan on what you want to accomplish and how you want to go about it. 18 modes plus 3 wizard modes and various multiballs gives you tons of options.