If your are planning on playing non 'cockpit' games (I. E thoose you won't be sat down wearing) I would recommend a rift or vive over a wmr headset.
Personally I would say you are missing out on a fuller experience if you don't get up from your seat. Games like Robo recall on the rift are a real blast.
My preference would be for rift with an extra 3rd sensor for improved tracking if you have the space for a bit of roomscale. Reasons are arguably best hand controllers at the moment, good tracking (especially with third sensor) and a relatively good balance of price, FOV, and resolution
If you definetly don't or can't do roomscale a Wmr headset might be worth it for the lower price.
Advantages acer
Cheaper
Lighter
I think it has a flip up screen that allows you to keep the headset on but still see?
No need for external tracking sensors
Slightly higher res then standard vive or rift
Disadvantages
Head tracking generally inferior to a well set up external tracking system
No external tracking means means inferior tracking for handheld controllers especially if you are in a room with a lot of other light sources. Also tracking fails if you hand and the controller isn't in line of sight of the headset. You have to be looking at the held controller to get good tracking unlike rift of view.
Handheld controllers generally inferior to the rift ones
Narrower FOV
I don't think there is a wireless ad on option like there is for rift and vive? (but the options there are expensive)
Suffers from more motion blur due to screen type