Desert Eagle: To tiger stripe or not tiger stripe? Gold or silver? It's a very tough decision.
The ones I've found don't seem to offer ambidextrous/reversible mag releases.
Reversible mag release? I am not sure that's an option for the 1911. Get on the 1911 Forum and poke around.
If I decide to go the 1911 route, what is a reliable one for around $800 that is lefty friendly? The ones I've found don't seem to offer ambidextrous/reversible mag releases.
"Low cost" and "1911" don't go well together.
I have had excellent luck with current production Colt XSE series pistols. My Colt WWI fed all common JHPs and shot very well.
I have had terrible luck with Springfield Armory (EMP, Loaded, Operator) but SA Customer Service were able to fix the reliability problems. Details are long and involved and I was very, very annoyed when consecutive purchases were lemons.
I had an awful experience with Kimber. The guns were unreliable and their customer service department did not follow through on their promises. Springfield Armory's shop at least did what they said they would do and didn't cut corners.
You could get weird and go with 9x23mm. Now that's a hoot to shoot when your bullets push 1600 FPS. Respect ma authoratah!
Your best bet is likely a semi-custom gun from Ed Brown or similar.
Someone is going to recommend an Rock Island Armory 1911 for $400. All I am going to say is that two examples I saw in my LGS had mainspring housings with chisel marks. If you find this acceptable, carry on!
Good luck and have fun with the 1911! It's an adventure I undertake once every five years that lasts a few months. It can be a fun ride.