Don't really follow particular dogs...
But something to look out for is fast beginners.
They don't put the sheets up in my local pubs, but they do at the tab. It's bellow the fields and they indicate by little arrow heads how the dog begins and it lets you know wether they jump R (rails), W (wide) or M (middle).
Obviously the ones with the arrow head further to the right are the supposed fastest beginners. I've got a lot of nice little exactas by picking 2 of the 3 fastest out and picking them in order with regards to box and wether they jump wide or to the rails etc. Or if they have a couple of slow beginners beside them.
If at the pub, they put the ratings up on sky in the bottom left of screen before the dogs races. They have the 3 'speed' rated dogs in order with arrows aswell.
Getting to that first bend and out of the traffic is very important
