I finally did my choice : I bought a VS2. It's working very well, I didn't have any recocking problems yet.
PS : I made this thread because there's alot of bad information said on the MR and VS series. Please refer here before speaking about wrong information. I don't want to flame anyone here (most people here are great guys), but the only thing I want is to help others with good informations. What is said in this thread can be found on the official site of spyders.
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