I looked into changing the LNB but thought a box would be easier. Would the LNB you've posted above still work with Sky Q? I assume I would need to swap the cables back or fit an extra cable for the freesat?
The LNB above won't work with SkyQ, it's purely for the old SkyHD and older Freesat boxes like the one you linked.
The old style LNB's basically 1 output can feed 1 tuner, to watch/record 1 channel at a time, so e.g. Sky+/HD used two outputs so you could watch 1 thing and record another.
The latest LNB's output a wideband signal with half of the signal on 1 cable, and the other half on a 2nd cable. The benefit being that all of the channels are available at the same time through only 2 cables, so it's just up to the box manufacturer to include enough tuners to watch/record as many concurrent channels as required (e.g. 8 Tuners in a SkyQ box, 4 in the latest Freesat 4K Recorder).
There are hybrid tuners available (i.e. that have 2 SkyQ/Wideband outputs, and some legacy outputs), however they can be hit or miss, in that some of them would only work in SkyQ/Wideband mode with an actual SkyQ box, and wouldn't work with the latest freesat box).
If you changed your current Wideband LNB to the "old" Quad LNB above, you'd keep your 2 cables, but only use 1 of them for your TV. (The 2nd cable could be used for a TV in another room with an extension cable, or you'd use both cables with e.g. an older Freesat Recorder e.g. one of the Humax models than can be picked up used from the highstreet second hand store)
If you later resigned up for SkyQ, they normally send an engineer out to check your dish and would change the LNB back to a SkyQ (or maybe a hybrid if you asked) free of charge.
