XY, he's never played serious minutes in a half-court team so it's guesswork at this stage, whereas Madgen had a standout season in a very structured team in 2012.
Remember also, Sobey's breakout season has come in a year where the refereeing is strongly in favour of the offence and his team plays the fastest in a fast-paced league. Cairns and Perth would be amongst the faster teams in many European comps.
There are a lot of adjustments he would have to make playing in a good European comp, he'll have to play differently and I don't think he has the experience to do that just yet, especially under import pressure.
As I said he could start in a lower league, but he'll be playing in a lower standard than the NBL, most likely getting less money and risking stalling his development if he doesn't fit the style and ends up sitting.