Big Truck looks to me to be a bit out of his league with these. I think the morning line on him is 50-1. Big Brown, the pre-race favorite, on the other hoof, looks like a potential monster! BUT, he is very lightly raced (fresh?) with only 3 prior starts and will have to overcome the extreme outside post #20 in a field of 20, while avoiding getting caught up in an early speed duel with other speedsters in the race. And with a field of 20, there should be at least a couple who will challenge him for the early lead. His jockey, a very smart and experienced one, though, says he will try to 'rate' Big Brown a bit off the early leaders.
The last horse I saw with his incredible abilities and running style was the filly Ruffian. Ruffian would always get to the lead right from the gate and steadily increase her margin as the race went on. If you watch the (free) videos at the KentuckyDerby.com link I provided, you'll see what I'm talking about. This horse really has been amazing so far. The second choice in the field, Colonel John, is a powerful closer who figures to be right there, or at least to be in the money. The good thing about these very large fields and enormous betting pools is that you are almost assured to get a better than average payout. And this includes the Place and Show pools. In other words, even Big Brown would likely double your money on a Show bet. And he would only have to finish 1st, 2nd OR 3rd for you to collect.
Regarding Pyro, who's trained by the same guy who trains Horse of the Year, Curlin, nobody seems to know what happened to him in his last race where he disappointingly finished 10th. I had liked him a lot up until that poor and unexplained performance, although the winning times for his victories weren't really impressive. ie. 1:44+ for 1-1/16th mile. Quality times should have been closer to 1:42 for that distance. Still, I would not be surprised if Pyro rebounds and comes storming down the stretch late in the race to grab a part of the purse.
One word...polytrack. I expect him to return to form now that he's back on dirt. I'm going to couple him with both of Bill Mott's horses, Court Vision and Z Humor.