I owned a 12" DeWalt non sliding miter saw. It was great I sold it because I found a Kapex on FB Marketplace, sent it in for a full service and used it for 3 months. I sold it and bought the DeWalt with the XPS light again. I was using a CT26 with the upgraded hose diameter on both saws. The dust collection difference IMO is negligible. I sold the Kapex, bought the DeWalt miter saw and used the extra money for other tools in my shop. I have a track saw that I use for any wider cross cuts than my miter aw can handle, which isn't often.
I really wanted to like the Kapex, I have several sanders, domino, routers, saws etc. so I'm a festool fanboy of sorts, but I really wasn't very impressed with it....The Kapex is also the ONLY miter saw I've ever used that I experience kick back with. Probably user error, but worth nothing. It happened a lot with the Kapex.
Anyways, that's my two cents. I love my DeWalt, I'd get a DeWalt or Milwaukee slider but I need it to sit flush against my shop wall so that wasn't an option. Hope this helps.
My use is primarily building furniture, NOT trim carpentry. So my use case may not be the same as everyone else.