It's not a bad game by any means. But if you're planning to play it on your own without a friend, you'll probably have a lot to complain about. Comparing it to SR2 and SR3 yea for sure both games were a lot better, but just like any game I play it eventually gets boring to repeat the same mission over and over, even the best of games like GTA 5 , red dead redemption, spider man, etc. The only games that don't get boring after extensive repetition are the online competitive ones, at least for me. Like SR2 & SR3 I'm sure I'm going to beat this game once or twice and put it down.
Graphically it's obviously way better than it's predecessors, gameplay wise it's certainly not as funny and compelling as the older titles. But as I've mentioned I didn't play this game on my own, and instead made an effort to 100% complete this game with my buddy who I beat most games with. Were we blown away? No. Did we comment on all the bugs and repetitive missions? Yes. But did we have a laugh and a half doing it? Yup. So it was worth the money for me. There's few story mode based games that I actually spend the money on, and when it's a big name like saints row, you just do it. Real Saints Row fans don't let negative reviews stop them from buying and beating the next game.