I might retort that I haven't heard much Wersi stuff that I am very impressed with (other than great players simply PLAYING them!), and very little Yamaha stuff sounds remotely 'live', very little Ketron stuff that sounds remotely contemporary, and Korg's issues with few fills are well known.
But all that would do would be to annoy users of those particular arrangers, and still be just my (and a few other people's) opinion. But I'm SURE, seeing as it's you, Bachus, that it must be a FACT, not just your opinion, eh?

Truth is, there is NO 'perfect' arranger... They ALL have certain issues. Including Roland. But an 'unrealistic' or 'artificial' sound isn't one of them, IMO. For starters, short of B4 in a VST arranger, the G70/E80's Hammond sim is easily better than most. It's grand pianos are by FAR better than most, and the drums simply have no equal for a good 'live' sound (having been ported from the TD-series drum kits - drummer approved!).
I play regularly in live bands, so perhaps my ears are a bit more used to that particular sound and dynamic that most home organ players, but whatever... If it's not for you, it's not for you. I admit that OOTB, the Roland's aren't necessarily as polished as some, but the raw stuff IS there for you to customize to YOUR tastes. Given your preference for Yamaha's and Korg's, I would simply say that you and I have a VERY different idea about what 'real' and 'live' sound like.
I played with two different live bands this week... and every one in them was blown away by how realistic the G70's sounds were. Maybe it's the gear, maybe it's the player, who knows?

But so far, I haven't heard anything on another arranger that has even remotely made me go 'I GOTS to have one of these instead of my G70!'...