Having tried out all the preview builds on a spare laptop here, I think I'll wait for MS to finish Windows 10 properly before I use it. The final RC was still very messy, certainly to the level that I highly doubted all the bugs and inconsistencies would be fixed before release (just not enough time left). Basically, my findings very much mirrored
These.
Also, El Reg has had numerous articles up lately about bugs, crashes and other such issues, so I reckon I'll wait a bit until 10.1 comes along and Microsoft actually fix it. At the moment, I just can't help feeling that they'd committed so much to this release date that they found it preferable to release an unfinished product, rather than push the date back by a month or so...