I am considering changing from my plastic QE to the wooden rimmed metal ones. My frames are flush with the tops of my boxes, so there is no bee space between frames and plastic QE. If I switch to metal ones, do I need to worry about the bee space created?
Don't worry, that space is there deliberately -
note that the rim only makes space on one side of the wires.
For your "bottom beespace" hive, you want that rim/space
under the wires.
For top beespace hives you wouldn't need to buy a different version - it just gets used the other way up -- creating a beespace between the wires and the bottom of the frames in the box above.
You can buy (for about £6) a metal 'comb' which makes cleaning the excluder wires much simpler.
When removing the QX, be gentle with it, don't try and lift it from one corner! The things you risk breaking as the QX bends are the corner joints in the rim.
If you are going to be careful with the rim (so it lasts forever) then you might be interested to know that Thorne have (this year) introduced a version with stainless steel (rather than galvanised) metalwork.
These rigid-wire QXs are much much better than the sheet types. The problem with the sheets isn't just getting them off, its cleaning everything so that you can replace the thing.
You won't go back to them!