Yep, I actually bought a MBP last year just so I could use Scriv.
Very good piece of sw – does loads of things which is IMO both good and bad. The good; provided you have the time and the inclination, you can organise your material pretty much however you want. The bad; if you have a lot of material then you may well get fed up with the time and effort it takes to manage it and wish you hadn’t bothered trying to be clever and resourceful in the first place.
Gave it a good run out for 3-4 months but found I wasn’t taking enough advantage of the Scriv-specific features. Tried loads of other sw (Mac and Win) but couldn’t find anything as capable. Reverted back to using Mind Manager 8 (Win) for organising everything, and just using Scriv to write the book.
Then got irritated by using Mac and Win … so ended up using Word and MM8 (both Win) and putting the whole Mac/Scriv thing to one side.
A Win version has since made it to beta (is buggy for some) even though this was never the author’s original plan SOB. Have tried this but it’s not as slick as the Mac version.
Hence I’m still with Word and MM8.
Having said that, it does depend on what you’re writing, the resources you need, the way you organise/structure, etc.
Very solid piece of kit though and fairly well supported – download the trial and have a go.