When I bought my DSLR a few months ago, I also bought a small, flexible tripod to put it in my photo bag as a backup when I have my good tripod not in range. After some research on the web I decided to buy a GorillaPod SLR-Zoom with a GorillaPod Ballhead which is capable of holding up to 3 kg according to Joby. But on the first tests I noticed that my Canon EOS 7D with a mounted EF 70-200 f/4 L IS USM lens is too heavy for this combination to work properly.
A few weeks ago, a friend of mine decided to buy a small GorillaPod for his compact camera. So I took the chance to sell him my SLR-Zoom and bought a GorillaPod Focus with a GorillaPod Ballhead X. This combination is made for up to 5 kg according to Joby and the ballhead is compatible with my Arca-compatible Camera plate from Kirk. Yesterday the GorillaPod Focus arrived and so I had to chance to test it. It is much more stable then the SLR-Zoom and for a decent DSLR the GorillaPod version to go for. If mounted correctly, it has no problem to hold my EOS 7D with the mounted 70-200mm lens. The disadvantage of the Focus is, that it weights 762 g (with the ballhead) instead of 391 g and it is 35.2 cm height instead of 31.8 cm. So you have to carry a little bit more and it may be difficult to fit it into the photo bag.