RE: WALKERA 37
I am really new to these helis and I bought this just searching the internet one night so I don't know very much about the others. This is a good machine now but if you get the stock brushed motor and battery its pretty much un-useable. It needs the burshless motor and Lipo battery. I did modify the stock push rod. I shortened it slightly and used a pair of wire cutters to make indentations on the end so the glue would hold. I used JB weld and I can't pull it off. The other end is still adjustable. It worked perfectly on mine.
I wish I could be more help with the other models buy maybe someone else can chime in.