Can't help with anything about the Sling Monitor 150- has that even been released yet ? Just don't know enough about it.
Regarding your second question, I'm not sure I understand what you're asking.
If you want to use an AP Express as a wifi bridge to connect your Slingbox to your primary router, then YES- you can do that.. It can be a little tricky to set up, but it'll work.
Your cable box (or any other compatible video source) must be connected to the Slingbox. The Slingbox in turn must be connected to your router.
The only networking option for the Slingbox is ethernet. However, there are three ways you can pull that off:
- Use a regular ethernet cable. Do it the old fashioned way. It's reliable and cheap with good performance.
- Use powerline ethernet adapters. These are ethernet bridges that use your household electrical wiring to connect things instead of normal cable runs. Slinglink Turbo fills this role, and they are compatible with some other brands of powerline adapters.
- Use a wifi bridge. Wifi bridges have an ethernet port on one side and a wifi radio on the other. AP Express can be set to do this, and there are several bridges available from other companies.
Hope this helps,