Saitek used to be good. Then around 2007 maybe, Mad Catz bought them and the quality dropped. Then in 2016 Logitech bought them and the quality disappeared completely. Logitech have cut corners to increase profits and the reputation has suffered.
Reviews on the x55 are primarily mixed due the large number of faulty units people have received. It should be noted that newer units seem to be having fewer issues and it's possible the initial batch had a lot of faulty units with the newer batches being improved.
The x55 comes with 4 springs of varying resistance's to enable you to customize the force required to move the stick. The x55 also works with no springs at all, giving you 5 different resistance options.