I would suggest if you think you might want an LSD, go for it from the very start as to change it out would be a b*******, if my experience of getting it in is any guide
FYI Sport 250 does not come as standard with an LSD, its an option, in my experience.
I would not read to much into what the press say, there are people on here who are a much better judge of the WF family and a few 250 owners who have made it to the road. My view, and it's my own as my 250 is still in-build, is that any jurno is going to be bias from his own experiences, and lets be real here, not many of them love the 7 family, and would naturally compare to production cars, and IMHO thats not the only part of WF ownership.
I took a lot of time looking at 7 type cars, and the best advice I could offer would be to have some idea of what you really want to do with the car, and then get along to a local group meeting and have a chat with them, you will probably get more from that than you can imagine.
Did you have a budget in mind as this might really determine what is possible?
I don't think any particular model in the range is any easier than any other, maybe just more bits to start with, but at the end of the day its a space frame chassis/engine etc. with a lot of variables down to choice.