To me the SP140 frame looks like a modified Air Conception aluminum Delta frame. The Delta is a very light frame and still very durable. That is just what it looks like to me.
I have had no electrical problems with my X4 batch 3 build. You arm it, press the throttle and the props spin. It is a dream to fly…so much fun, and it lives on the back seat of my car! Also, no torque steer and very little maintenance. I did abort a takeoff the other day…took a knee and broke 2 props. It was a new LZ to me…the launch was downhill…and I ended up getting some trash in 2 of the motors. A little compressed air should take care of it. If you are a “maker” and a 20 minute flight is ok with you, the X4 is a great machine.
I have built and flown quads for years, so, I was already familiar with charging lipo batteries. I am very good to them and only charge them to 90% and discharge to 20%. My batteries are great and hopefully will last many more flights…they are solid and look new still.
Electric is the future.
Here is a link to my build:
I hope this helps.
Bill