I would keep your expectations in check.
Sure, aesthetically, they appear to be very similar: colorful mascot brawler, but the game play is very, VERY different.
I also expected it to play like Smash. It. Does. Not.. Initially, when you are first booting up the game, and in control of a character, and you start playing around with the attacks and what the buttons do, you're like, "Oh, yeah, this is totally like Smash! I got this!" Then, you start to try and play the game like Smash, and suddenly you aren't doing so well.
It's a bit of an oversimplification to say that your goal is to build AP to execute a Super, but then again, that's what makes games like this so fun, the goal is painfully, obviously clear to you. In Smash, your goal is to attack your opponent to build up their percentage meter so you can smash them out of the ring. Devilishly simple. But the HOW is where things get complicated. Other players have their own tactics and strategies. Characters have their own sets of moves and counters. It's a back and forth.
When a PBR match starts, yes, you are trying to hit that guy and build super. You get a Kill, you get 2 points. Great! But then, another player kills you! Crap, now you're down to 1 point, because each death subtracts 1 from your score. Dammit! He got another kill! Now he's up by 3 points, and you are still trying to recover from that death. But there are two other players in the match all trying to do the same thing.
It's no less chaotic in FFA in PBR as it is in SSB. That back and forth, ebb and flow, attacking, countering, executing supers, dodging supers, is just as exhilarating here as it is in SSB. The middle game is where it tends to get really exciting, when each player has gotten a few kills and deaths under their belt. It then becomes a matter of diminishing the leader's kills by killing them, while keeping your own kills untouched.
It's fun. And very different than Smash. I enjoy that both have a very different meta game in place, and both are very fun.
I know my posts will go ignored, but they are here for anyone wanting to bother to read an informed opinion about the game. And not just an informed opinion by a PlayStation fan (which I am, no doubt), but by a Smash Bros fan as well.