when you see an rc helicopter flying it makes you feel like you can just go and purchase one and fly your self but when you go to a model shop to purchase one then you realise that they are not cheap so you then try the next best place and that is online auctions and they sell mass produced helicopters for far less money.
but wait the reason the model shop will sell the helicopter for alot more money is because of the equipment fitted to it so it will fly safely.
most ic nitro fuel helicopters have a head speed ie rotor speed of 1500 to 2000 rpm now when cheap electric equipment is fitted and you fly then this equipment is under alot of strain and can fail and cause serious injury or even death to you or others around you.
this is the diffrence between model shop helicopters and online auction helicopters its not so much the helicopters but the electrics that are fitted they just aint up to the job.
now i dont own a model shop but i do fly helicopters and have done for a few years now and i done it the dear way by getting help from people who now and it helped me learn safely how to fly and whats best to use to fly.
a servo is a device that is part of the control of most models and they can cost from £4 up to £100 now if you put a £4 servo in a car it will perfom ok but not brilliantly but it will be safe but if you put the same £4 servo in a ic nitro heli then it will be under severe stress and will prob fail and make the helicopter crash but if you put an £50 upward servo in the helicopter then this will be safe enough to fly this is only one of the reasons the model shop helicopter will be much dearer than the auction one.
basically to cut my story shorter dont scrimp on ur safety just to get a helicopter in the air or other peoples safety as it will be your responsability of you seriously injure some one or there property