here is my 2 cents from todays experience. i too want to watch/control my solo2 from upstairs t.v, so i went to asda and got a wireless video sender with ir.
based on the performance i will be going down the rf modulator route.
the upstairs tv is directly above my front room, wireless from my router caused interferrence on all 4 channel freqs, (resolved if i stopped the broadcast,)
the solo2 remote ir will not affect the box itself if the sender is powered up, (works fine from upstairs) but would be a hassle to turn on/off everytime i want to watch tv upstairs as the main sender unit it now behing my tv that sits on the wall (wireless range is rubbish)
i will be going down the rf route for sure.......
for reference the make and model i used >>>> SLX Comapct AV Sender only cost me £30, wish i went for the 5.8GHz now for the extra £20 :/