I have played the Avengers Pro and I like the machine. Cabinet art, translite art is amazing. Playfield art is very good.
I will say honestly, that Steve Ritchie and John Borg are better designers than George Gomez for my style/desire of a pinball machine.

George Gomez seems to always like straight shots on a playfield versus the style of SR or JB.

The top right corner of the Avengers is a little hard to see, and the game does need some leds instead of std bulbs on alot of the side inserts because they can be hard to see in a very lit room. So extra LEDs would be my first mod. The captain america inserts x 4 are easily visible, and the red arrow is half visible, but if that bulb was replaced by a Led, it would be much more 90 percent visible.

I need more time on the game, but i am confused because both the inner rollover lanes inserts cannot be seen at all because the plastics cover those 2 x inserts completely.??    Because u have to light both the inner and outer rollover lanes near the flippers to advance thru the game, I am perplexed as to why these inserts cannot be seen when standing in a normal playing position at all ???.........

Remembering that this Timezone machine is a test mule, I dont know if the plastics are the finished version or not....but as I said, I have to spend more time on the machine and look at it properly without 500 kids around, and without massive bright lights shining at the machine from every different position. The machine has a slight Transformers feel/look to little bits of it and the playfield etc, but basically it is a very nice package...
I have to spend more time playing it to do a proper assesment/write up. Gameplay is fun.

Would I buy one ? YES. 
DMD annimations are good, sounds are great.....just have to work out a few shots on the playfield and why the inserts for the bottom lanes are not visible.....I would have thought that would have been pinball 101 to have plastics there that are at least partly see thru, versus blocking those inserts....something isnt right unless I missed something with the very quick 5 minutes I had with the machine whilst others were already playing it...stay tuned for more info.

Brett