I went hunter with bow gun, ranger with grav gun, sheriff with auto shotgun, and sniper. I'm at day 144 so far, haven't found a decent bow gun or grav gun with more than 1 mod which sucks, but both the hunter rifle (over 440 dmg) and auto shotgun (2 anti-armor, dmg, 2 reload) have 5 mods each. That sheriff easily gets mvp of my team. The grav gun was great early on but it's the sheriff that keeps my wall untouched and racking up perfect games. I think the game puts too much emphasis on finding the right gun and mods.
One cheesy way to beat the game is go with the minimum of letters in the boiler (20) and stick to more common letters in the alphabet (the level 1/2 Jade/brass letters keep in line with this strategy). I end up using only aaaeeedillnnorrrsstt as my letters and transmuted the rest to get those jade/brass.
The game didn't turn out to be that fun afterall :( Mash out those long words and those chamber letters tend to be all used up.
Haha 390 continues. Terrible game. I was thinking that it's possible every time but required perfect timing until the last level I ran into a wall (top and bottom column touched). I guess you just gotta get lucky.