lol using the same starter sound is done a lot. hell useing completly the same sound FOLDER (that being a on a off a eng sound MG sounds wind sounds bomb sounds etc.) is done in every sound pack i know more than once.
Listen to what Ack-Ack is trying to tell you, as I did before - Just because you mix a few soundpacks does not mean its your sound pack. You need to design or capture the sound YOURSELF, and believe me its a bit harder then you think.
Do yourself a favor, if you want to post your mixed pack - LIST all the authors you took the sounds from, this will save you the retribution of getting caught later passing off stolen material.
Remember as I said,
I have my own sound pack which is 80% of mixed and 20% mine, I wouldn't bother posting it unless it was 100% mine, another good reason is the 20% is mixed vehicle sounds, and not 1 vehicle is "complete" just a bunch of different engine start ups.