I think the '08 bikes had the upgraded cam chain tensioner installed from the factory.
It's part #9 in this pic:
The main difference is that it has a built-in oil reservoir, which is the large cylinder at the top (right next to the 12 in the pic).
If you look at this pic:
You can see the new tensioner in the top right corner, nestled between the frame rails. It's the black cylinder with a white sticker with a small BMW logo.
The old style tensioner was just a flat plate covering that same hole, with no upper cylinder, so it's pretty easy to tell just by looking at it.
Just remove the right side fairing panel and you'll know.
That upper pic also shows the cam chain jump guard as part # 17, but the lower pic doesn't show the jump guard installed.
One thing to do is to make sure that your bike has had all the appropriate Recalls and Service Bulletins done. A good dealer will already have all that sorted, but it's worth double checking when you pick the bike up.
As for fuel strips and ABS, I never had any issues with either in 138,000 miles on my '07 GT.
'13 Dark Graphite Metallic K16GTLD, 24K miles and counting...
'09 Magnesium Beige Metallic K13GT, 60K miles miles and counting...
'02 Mauve Metallic K12LTC, 106K miles and sold
BMWLT#145, IBA# 366, MOA# 111996, SCMA# 24032
All lower 48 states plus Alaska on the K13GT in two weeks . . .
Some people see the gas tank as half empty. Some see it as half full. All I care is that I know where the next tankful is coming from...