I'm not a huge fan of the shin guards on Full Throttle, but they don't bother me that much. It is better than having the hangtime limited with OTSRs.
The one time I rode X2, it was horrible and my head slammed against the back of the seat several times and it made me never want to ride it again. I love Viper and think it is one of the best rides in the park. It is long, intense, and leaves me satisfied. It is a little rough, but I'm so tall that my head is far above the restraints, so I don't have any serious issues with head banging. The only part that is really rough for me is the double loop since it jolts your neck back between the loops. Outside that, is a fantastic ride that might be in my top 5 for the park.
My favs at Magic Mountain are Twisted Colossus, Tatsu, Batman, Apocalypse, Viper, and Ninja. I love Arrow Suspended coasters so I really treasure Ninja.