From the research I've done on the BVM, JHH & Yellow A-4's, their all basically the same plane. The A-4 has gotten a bad reputation as a bad handling plane. I've talked to many people who dog it, "snaps in a turn without any warning", "snaps while landing with little or no warning" Etc... The one thing all the bad rep's have in common, heavy plane 11 to 14 lbs. and / or, Yellow A-4 with big engine. I also understand the Yellow does not have the washout that you build into the wing of the BVM/JHH. That also seems to be a BIG factor, as some have put the bigger engine in the BVM/JHH, and not had as many problems. The big engine/Dynamax adds 1- 1/2 lbs., not to mention the extra fuel, which ups the wing loading dramatically for this design. I would gladly give up a few mph for a good handling jet, that will last more than one or two flights. If I want all out speed, I'll get out my diamond dust, I haven't seen a ducted fan jet that could hold a candle to it. All this information has been gathered by me, over the last year or so, from many different forums, jet list, conversations, etc... Keep the weight under 9-1/2 lbs., don't let it loose too much speed in the turns, if you want more top end speed, sell it and get a plane designed to carry the extra weight.