Not likely. My place of work ordered a new mac mini. I hadn't realised I couldn't revert to SL since I had been able to boot into SL via my FireWire drive. To cut a very long story short, I had erased the entire drive, then after getting an error saying i could not install SL, I tried to g

et back to Lion. So i used my Lion USB drive i had created (which has been able to install Lion on 2 of my macs at home), but got a prohibited symbol (round circle with diagonal line). I then used my other FireWire drive with Lion installed on that, but got the same prohibited symbol yet again.
So I called AppleCare and they told me to hold cmd+r on boot (which I had already tried but received an error telling me to restart the mini). When the rep realised it wasn't working, he tried to blame my network connection or the hard drive. However we confirmed that both were actually working fine. The mac would connect to the apple servers (confirmed by my router logs), and managed to download the boot environment which took about 3 mins. After the download completed, the mac would restart, then commence the installation but kick out an error almost instantly asking me to restart/reinstall.
In the end, i had to take the mini to the apple store. The 'genius' then connected his 'diagnostic' FireWire drive to the mini to boot it up. Low and behold, he got the same prohibitive sign. Basically he got the same error I had, but confirmed the hard drive was working fine and healthy. Oh and he wasnt able to support my method of using my USB drive to boot into the mini which didn't work anyway since i got the same old prohibitive sign.
Guess what he did...
...
...
NEW MAC MINI.
DISGRACEFUL IMO.
Yes, I walked away with a working computer but the resolution should have been easy and potentially wouldn't even have been an issue if I'd had boot media or my Lion USB drive worked. Wonder if it's the same with the MacBook Air? I'm hoping this is a bug...