I recently went through this decision process between the Omega and Triumph. I decided on the stainless laminated(not the thumbhole) Omega based on info obtained here and elsewhere.
I've heard lots of good things about the Triumph but there are a few things I didn't like about it.
1. Its a break open gun but it doesn't close like one. You need to make sure that the breech plug is lined up correctly when closing the action and at the same time, you need to close the trigger block. I almost got my finger caught when closing the block. To me, it was too clumsy.
2. Price. I just couldn't see spending over $400 for a gun with a synthetic stock and blued barrel. The weathercoated barrel is on the outside but not the inside. For the same money, actually less money than the weathercoated/black composite Triumph, I got a stainless laminated Omega.
3. Last but not least, the Omega felt better in my hands.
Positives:
1. The Triumph is definitely easier to clean. I may eventually buy one based on this alone, who knows.
2. The range reports have been comparable to the Omega, based on what I read only.
Next year, T/C will probably introduce a stainless laminated Triumph but based on what they cost now, $500-$600 will probably be the price tag.
In any case, based on what everyone told me, you can't go wrong with any T/C gun.
Good Luck