I've used all the open source slicers, sfact , slic3r, cura, material matters (closed source I think, but free)
also commercial ones
Kisslicer and now simplify
Slic3r is good and was my coice of the OS slicers, however I had issues with rafts and support removal, Also would crash on larger STL files, not to mention looong slicing times.
Cura not a bad runner up, but not really wrapped with the interface, same again on support and raft removal.
Kisslicer has been my goto slicer for the last 12 months, still not so great on support removal, is probably the best for multiple extruder printing though. (haven't tried slic3R since upgrading mine to dual extruders though) but when the developer of Kisslicer went awol for some time I needed to look else where, found Simplify and the first thing I tried was support and raft removal.....Much better than anything else I've used, except the UP printers, their software has nailed this removal to almost like velcro.
I do prefer how Kisslicer handles filament profiles over simplify, but simplify you can have multiple profiles assigned to an object or multi objects, i.e. I can change the temperature, slicing, fill, wall thickness, speed, on any number of layers mid print though these.
I do most of my printing now on simplify, sometimes reverting to Kisslicer for things and every now and then I'll give slicer a go to see how things are coming along.
I'm finding most of my prints now days are in ABS and the brim feature is great for stopping the warping always associated with printing ABS.
In all if you like and use your current slicer, stick with it, but the time you are having issues try simplify, you won't be disappointed and well worth the money.
Just for something a bit different I backed an indiegogo project some time ago called print to peer, https://www.indiegogo.com/projects/printtopeer-your-3d-printer-on-the-web/x/4522351
, which is a RPi based controller and cloud based slicing, so will do a review once I play around with it some more.