Monster Hunter Generations Ultimate at an all time low (again?) seems like a good deal. Is gameplay similar to the other MH games? Good solid solo campaign?
If by the other Monster Hunter games you mean games before World, then yeah it's like that. But it's also probably the most dramatically different MH game because of the art and style system. In addition to a weapon you also pick a fighting style that lets you focus on a specific type of play (normal, aerial, high risk/high reward style, etc.) Then you have arts which are just super attacks, fill up a meter and then use a super strong attack or give yourself a powerful buff. How many arts you can equip is dependent on what style you play as.
As for solo stuff Generations has the biggest monster list of any MH game (almost 100) so there is a ridiculous amount of content. But there isn't much of an actual story, it's an anniversary game so the single player is mostly just traveling to locations from previous games and talking to old NPCs. Also of course keep in mind it's like older MH games where G rank is meant specifically for multiplayer so you can't really do everything unless you're willing to find people to play with or deal with massively inflated HP values on monsters. But you can easily still put hundreds of hours into the solo content if you wish, it's not like that part is lacking.