My favourite is Pedro Kantor, as I play Imperial Fists so I use him as my Chapter Master Vladimir Pugh. Fielded him in every battle I've fought so far and he's always been well worth the points he costs, heck he was the last man standing in my army in my last battle when I got massacred. I have a Lysander but have yet to finish painting him up, not a model I'm fond of and so he's been languishing at the back of my painting desk for over a year now.