Nice video! And congrats on joining the world of pure sailplanes. Some nice flights you had for a maiden. The Fling hi-start won't launch your BOT ARF. The BOT ARF is about 8 times heavier than the Fling. I have a 2-3M rated hi-start and it just barely gets the BOT in the air at 2/3 max tension. You should go ahead and buy the Aerofoam Hosemonster for 3M. You can get the complete hi-start or the tubing and build one yourself. Lots of threads on hi-start comparisons on RCGroups. Hobby Lobby sells a decent 3-meter rubber as well, but most people regard Aerofoam Hosemonster as best. If you are short on field length, Aerofoam has a shorter zipstart also. Hosemonster Link
There is great discussion on technique and equipment in this thread. http://www.rcgroups.com/forums/showthread.php?t=155353
Good luck with the BOT, and let us know how it goes. I might be launching mine on a winch for the first time this weekend and will be sure to report back.