Steve, go here for some advice/information on the ST1300.
http://www.st-owners.com/ Many riders rave about the ABS - they love it.
The only issue appears to be heat, some are HOT to ride. Ask the PO about it. I have a ST1100 and it's a great bike either solo or 2 up. Smooth, quiet and quite fast for me. I prefer the look of the 1100 over the 1300 but that's just me. It's an older guys sport bike and the number of accessories or farkles is endless. When you're shopping for a sport touring make note of what will get damaged when it falls over. Don't laugh, many ST owners belong to a not so exclusive club of slow speed tip overs. The bike is heavy and takes some getting used to. The ST's have tip over wings on the sides. The grey plastic things on the sides that hide "crash" bars. When mine went over in a friend's driveway I expected the worst - mirror, bags, fairing to be scratched. Nope. It just laid there on the edge of the tires and the tip over wing. Because I didn't want anyone to see the scratch on the plastic cover I paid the $28 for a new one. Other sport touring bikes, not so lucky. A magazine dropped a FJR and it was a $1700 repair estimate. The new BM'ers are reported to be a lot more.
And, I think the ST compliments my 750!
Cheers,
Cliff.