As a Colt and Sig 238 owner, I can only say, you will be glad you have a lifetime warranty with the Sig. Mine 238HD has been back to visit the factory 3 times now. They actually have owned the gun more then I have since I bought it.
I will be heading to the range tomorrow to see if they got it right "this" time.
Back to your Colt.
Yes, the trigger is plastic and yes some parts are a bit "cheesy" but it will likely work out of the box. That is more then I can say about the SIG. My Colt 380 has been 100% reliable from the day I bought it. Great gun, accurate, reliable. I just wish Colt still made it because when I put them (the colt and the sig) side by side, the colt has distinctly better work where it matters. (Night sights are not what matters when the gun won't run).
For example:
The Colt extractor is on the bottom, while the Sig is on the top. Note how nice and sharp the Colt is cut and the extra chamfer on the bottom. This allows the rim to glide right in instead of hanging up.
The Colt extractor is on the bottom, while the Sig is on the top. Note how the colt is carefully cut and had a nice 90 degree cut while the SIG is rounded and actually cut obtusely? This allows the extractor to slide off the rim leaving the spent case in the chamber so it can jam.
So. When you get down to the brass tacks, the colt will likely have the better workmanship and parts then the SIG. I would buy the Colt over the Sig today.
By the way, I am not a Sig basher. I have SIG 210's, 229's and other Sport models and have been sorely disappointed in how far the company has fallen down on the 238. It goes to show you should not trust a company by its reputation, even with your own prior experience.