Some of your smaller profile and 4 size 3D machines mixed with proper thrust to weight ratios and propped correctly also makes a big difference do not require tons more torque than your trainner. They do require more but no where near 70 to 80 oz. Carefully select your first 3D bird and choose it on ease or repairs and initial build. They do need to be rebuilt especially if you are a novice 3D piliot. Servos shouldnt get too pricey in the 15 to 20 $$ range for each even some of the duel ball bearing standards will probably be fine for a 40 size 3D plane. I suggest a profile plane for ease of all of the above reasons. However to each his own. I have a Morris knife profile been flown for 2 seasons with a YS .63 on it. And I run all standard servos with 50 and 60 degree throws never a problem. Bottom line you can get all types of opionions in here as to what the best servo is but, no one person can tell you. Do tons of research read all posts and explore the ins and outs on the servos websites. I have a Funtana 90 10 lb 3D plane with a YS 1.40 in it and I use the Hitec 5475 Digital Karbonites $ 35.00 a piece 76 oz of torque @ 6v and its pleanty. But it took me a lot to get to where I was comfotable buying them. Theres just soooo much info on all the available servos and all of there pros and cons.