SW gets my vote.
I love the unique feel of its shot multiplier control and extreme risk/reward potential. My typical strategy is to build up the multiplier to a min of 10X before even starting to progress through the modes and focus on cashing in on shot values. Having to continually hit the 3-target bank to maintain a high shot multiplier is an added challenge in the overall juggling of sequenced shots.
The nice variety of modes and multiballs topped off by the ultra-cool hyperloop all contribute to an overall high stakes/adrenaline fueled game vibe!