any one use these? tripp is top of the line,IMHO. use their 8r. obviously stick out the bottom some. my 1911 is my in the car gun so i thought a few more rounds would be a good thing. not in a $ position to off the 1911 and replace with a sti.
10 rounders are typically less reliable than 8 rounders because the spring tends to strain under the weight of so may rounds. As you mention, they also stick out the bottom quite a bit. For trips to the range, I use 10 rounders to keep from having to reload as often, plus 10 is a rounder number than 8. This is a great article on this issue: http://www.10-8performance.com/pages/1911-Magazines.html
Now onto the answer to your question. I use Tripp 8 and 10 rounders and McCormick Power+ 8 and 10 rounders. In the last 2,000 rounds that I have fired, all of my issues have been failure to lock back and it has been on a single McCormick 10 round mag that I marked. It fails to lock back relatively frequently. Maybe once every five mag dumps (every 50 rounds). I need to just toss it. I tried cleaning it and replacing the spring to no avail. My Cobras have largely fired flawlessly, but I did have an issue with a FTF on a Cobra 10 on my first session with one. All of my 8 rounders by both manufacturers have functioned flawlessly. So basically, my experience backs up what Hilton Yam says, that 8 rounders are more reliable than 10 rounders.
Apart from that, I can't imagine a situation where you will need those extra 2 rounds. I can see 3 for a car jacker. 6 for a car jacker with an accomplice. If you have a Bangladeshi mob surround your car and try to flip it over, I am note sure that a handgun is the solution to your problem.
well yea,a car full of bangers with AKs and i'm screwed anyway. i really have nothing good to say about mccormicks. had 2 and both produced stve pipes in otherwise 100% reliable 1911s. likely stay with 8s,but just asking for input. thanks.