I have about 100 hours of gameplay time into KSP and I love it. Now, let me say that I like challenging games ... but the Spaceplanes in KSP are too difficult. I have watched numerous tutorials and spent no less than 30 hours in the spaceplane hanger designing different craft, but I have yet to be able to get one into an actual orbit. Personally, I have been able to fly one all the way up to 70,000 meters and get so, so, so, so, so close to an orbit ... but I just cannot come up with a magic combination of lift/balance/etc to carry enough fuel to get into orbit (let alone rendezvous). Basically, this aspect of the game is too hard -- I've spent almost a week of gameplay time trying to a spaceplane into orbit but that's the extent of my patience so I'm just giving up entirely.