Rubbers

Hey Alois, this is Jack your former student from School :). I stumbled upon this website purely by chance, when I was browsing videos of Olympic table tennis footage on YouTube. Just wondering if you could shed some light on a few issues that I am pondering over. 

1) What is the average lifespan of a table tennis rubber? (I am currently using Hurricane II and III which I purchased just over a year ago roughly.)

2) When would you consider it an adequate time to replace a rubber? As of late, I am experiencing a few obvious signs that my rubber is becoming defective, that is, there are parts of my rubbers that show no friction whatsoever. I can still generate sufficient spin, but there are notable inconsistencies at varying times. 

3) In your personal opinion, what would be a suitable upgrade of rubbers? As you might know already, I am a player based around consistency and if given enough opportunity, will smash the ball. I am thinking of possibly getting clean sheets of Mark V or perhaps even XS...but generally something that can impart great spin, whilst being able to maintain control over the ball. 

P.S: I think your website is awesome, I have been looking at many of the videos and have certainly gained vast amounts of assistance on my own game. Its great to see that it has been immensely successful for you! Take care.