If your sticking to dirt roads, get the DL650, if your going off/road at all, get the KLR650. The F650GS will be a little more dirt capable than the DL650, but the DL650 is the best for pavement and does ok in dirt.
Thats my 2cents.
Like all bikes, you need to test ridem and get the one that speaks to you.
2008 BMW R1200RT 7200 miles
2005 BMW R1200GS 13000 miles (Sold)
2002 Yamaha FZ1 (Sold) 11000 miles
2002 BMW K1200LTC 29900 miles (Sold)
2002 Yamaha VSTAR-650 Silverado (Sold) 9100 miles