Only tried them on other people's bikes, but I always find them really fat. 
Halfords grips for me - you get four tubes for £5, and each tube gets cut in half to make a pair of grips.  
Some halfords stock the old ones still, but the Loughborough one has these new ones. They're a bit thicker and harder, but after a few rides they mould to your hands and start to thin down a bit. 
 
 In my experience, I've found them the comfiest and grippiest, not to mention cheapest  
On the downside, the old ones rip, if you get them. The new compound seems better for not ripping however.