The W22s are meant to be as good as the M22s in all respects, including bass performance.... thats the whole idea.
I've got W3s and W150 that I put in myself. To mount them at an angle you will have to build a box off the wall with an angled front that they bolt into, probably out of plaster board and/or plywood. The retention indent is probably good enough up to about 15deg to stop them coming out.
The manual is on the product page... have a look and have a think about what you could do. I think the off-axis response is probably good enough that 15deg wont matter and you should put them in flat.
