Two dishes. Re-iterating some of what FaT Air has said, generally 6 to 8 degrees off-centre, or off bore-sight, is the optimal range. Naturally, some satellites can be further away, while some satellites you will find, due to varying transponder strength (usually the weak one is the one you want!), can't be anything than other than bore-sight, or very close to it. I would put both 97W and 125W in that latter category, for several reasons. As has been mentioned, 125W is DVB-S2, which requires stronger signals to begin with, and, as has been noted, some even have trouble with a bore-sight signal. There is also not a lot of "play" available, as there is with DVB signals. For example, with most DVB signals (depending on FEC rate) most can drop down to around 30% quality on my AZBox without loss of signal, whereas the NBC muxes on 103W have to be above 63-64% quality to have any picture without pixelation or total loss.
As far as 97W (which also applies to a lesser extent with 125W) it is the number of transponders and the varying strength of those transponders which make it not really a good candidate for an off-centre LNB. For example, on my 80cm, I did have 97W on bore-sight with 103W six degrees off-centre, but wanted to boost the NBC muxes (as one of them was very sporadic in reception) and moved 103W to bore-sight with 97W six degrees off-centre. However, I found that the loss to some of the transponders on 97W was very significant, and ended up having neither on bore-sight, with 97W about 2 - 2 1/2 degrees off-centre, and 103W about 3 1/2 - 4 degrees off-centre. Even that small amount of change to 103W was enough to bring the sporadic transponder up to just above threshold level (63-64), most of the time!
Don't get me wrong, I have had great success in experimenting with off-centre LNBs, and using smaller dishes (for example, my 60e dishes), but various factors must be considered in the choice of satellites for off-centre LNBs. For example, I have 72W at 15 degrees off-centre on my 75e dish and get the NBC mux there with good strength, but that is a very strong transponder to begin with, is DVB, and is the only transponder on the satellite that I required, so was a good candidate for experimentation (and did free up another dish for re-pointing).