I only ever take gust. Just too much utility on such a short cooldown.
Plus there is literally no better feeling in the game than having Epic Mount and seeing an enemy team start to run away from a fight and going behind them and feeding them back to your team. I love it

I'm not going to sit here and say Falstad is the best hero in the game. But I would rank him top 4-5 OVERALL for assassins. I mean he can't out burst a KT/Jaina combo, but he can 1v1 them and win, especially if hammer hits them coming and going. Lot of it is a preference thing. I just love his global on maps like Cursed/Blackhearts/Towers. His ability to kill an enemy 1v1 in lane and then be down on an objective in 3-4 seconds is just awesome.
But then again I'm at rank 5-15 where people don't realize how bad it is late game to let Falstad's hammer hit them 20-30 times in 4-5 mins in a lane. There are some games where the objectives force you to bunch up (like Infernal Shrines) where my hammer literally has 350-400 bonus damage by the end of the game.
Very few heroes can make plays late game like falstad can.
Li Ming is obviously insane late game as well but she requires enemies to be dumb enough to stick around on low health and let her just LOLSTOMP the entire team with 3 beams in a row + slow.
Either way, it's nice that the game is slowly having a wider and wider META pool. I remember when I first started playing in late summer/early fall and it was basically "Whoever gets KT wins"