Tires Tires Tires

[Big Lar]

Have a 2003 Boxster with Mich Sport PS2's
What would you recommend for just rears; they are worn to the bars
with little tread.Front still in good shape with treading.
I have 54,000 miles. This is the 2nd Pair of tires
1st was orignal stock Mich.
Would a different brand and tread design effect
handling?Should I change all four only if I go with a different brand?
I really want to change out just the rears.