The Remington has a solid frame/handle design, where the Colt has a frame with the handle part bring two pieces (backstrap and trigger guard) all held together with 6 screws. You do have to check occasionally to be sure the screws are kept tight.
The Colt is more common, and it's sometimes easier to buy parts and accessories. On most, the front sight is a bit high so that you can file it down to zero the point of impact - which is handy on a fixed-sight gun. You also have more choices in manufacturers, finishes, and barrel lengths.
Mostly it's a case of picking what you like best.