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I was a Kickstarter backer of the XPlusOne VTOL aircraft, and I was able to get it for $199 as an early backer.  Now it's sold at the regular price of $1,549 for the version I have, which has no autonomy (it's got a simple MultiWii controller board), or for $2,199 for an autonomous version with Pixhawk. 

I haven't tried the second, more expensive, one, but have now flown the first enough to give a quickie review. 

The promise of VTOL aircraft is that they can take off and land in small space like a copter, but have the duration and lifting power of a plane. Sadly, this is usually more true in theory than in practice. VTOL aircraft like these are often called "sporks" for a reason. As copters they are hard to control, unmaneuverable, and prone to being blown around by the wind due to the sail-like cross-section.  As planes, they tend to be draggy due to the extra props and as a result also struggle with the wind. 

The XPlusOne is no exception. As a copter it tends to be blown about by the wind, as you might expect for something with four (!) wings. But the idea is that you keep it in copter mode just long enough to take off and and land, and do most of your flying in plane mode. Unfortunately, the XPlusOne is even worse at that mode. Since it has no control surfaces, all steering is done with differential thrust of the props, which is sluggish. And since it has no tail surfaces, it has to fly with a very high angle of attack at all but top speed, which means that it's always close to a stall and thus also prone to being affected by wind. 

But the main problem is that, as you can see in the video below, it's almost impossible to see its orientation. With four wings in a symmetrical configuration you just can't tell which side is up, or left from right. Combine that with very poor control authority and you'll be lost within seconds of going into plane mode. 

I just got a few flights in, and only one in plane mode, before this caught up with me. On a windy day, i went to a safe altitude to transition, went into plane mode and I immediately lost orientation. So I switched back into copter mode and the winds at that altitude just blew it away to parts unknown in seconds. I was never able to regain enough control to bring it home. Bye-bye XPlusOne. Had I paid $1,549 I would have been pretty annoyed. 

In short, I think the XPlusOne is unflyable in its base MultiWii configuration. That said, a proper autopilot might have done a much better job than me and the Pixhawk-based version with GPS might have been able to bring it back against the wind in a way that I, from the ground, could not.  But I'm not going to pay $2,200 to find out.