I tried both Swift Key and SlideIT and ended up buying SlideIT.
Why?
It's just a bit more fun to use and has a slightly more "wow" factor when you show folk.
Swiftkey is good if you text in a certain way. It's like predictive text but with whole words, It scans your text messages and tries to work out your style of texting and away it goes. Very useful if you text similar stuff all the time.
For example, Are you out tonight, can be 4 taps, Press the A and it will suggest the word Are, confirm, then it will suggest the word you, Confirm and so on... It is good
As for slide it, you need to be vaguely familiar with a qwerty keyboard as your finger or thumb will be in the way, but you just start at whatever letter and simply slide to the next letter. I like this as you don't have to be that accurate and after a few months, my messages are now really quite quick. I find myself deliberatley using longhand as it's good fun
As for the access requests.... What harm can it do? Really? In this big wide world, do you honestly think that whoever is gathering that information is REALLY interested in little old me or you?