I am actually reluctant to buy any case as I don't like the idea of opening the case to view the phone but from my current ownership of a dumb phone I noticed dust particles get into the LCD layer and it gets worse over time in my jeans pocket-though not that much of a problem, having sporadic dust particles on the screen does worry me. I noticed that the dust entered through the one edge of the screen I think. A screen protector will not solve the problem as this is more likely a manufacturing defect hence only way is to go those leather protectors. I have narrowed down to two cases:
Premium Black Flip Case + SP - Samsung i9100 Galaxy S 2 on eBay (end time 06-Jun-11 07:58:43 BST)

SAMSUNG GALAXY S II S2 I9100 SII BLACK HARD CASE COVER on eBay (end time 14-Jun-11 07:20:56 BST)

The difference between the first and second type of casing is the first casing is in a bumper type of case, the second only holds the phone at few locations. Owned other pieces of tech in the pass and bumper cases adjacent to screen is great at trapping dust though I am not sure if dust will get into the screen in the first place.

Any thoughts on the cases listed here? Also, will the magnet case covers actually degrade the phone performance? The only case I can find from Samsung's website is a leather belt pouch which I don't really like-brandishing the phone in public.