Dude!  Are you planning on smashing into a fucking tree on a daily basis or something?  Sweet Jesus, get a grip man! 

Unless you have young children, or have the cash for a nice car with some decent airbags and proper chassis (you don't); then I'd just stop worrying.  There is risk to everything, so go and buy a suzuki swift, brother had one * it was a great little car. 

Ask the mechanic to show you where the offending rust is.  As I said, to fail it has to seriously impair structural integrity. 

BTW that picture looks shitloads worse than the last one you posted. 

Look here:

http://www.motester.co.uk/mot-cog.html

Can anyone who lives in Manchester go round to his house and Give AT a shooing , er I mean some advice?  Oh and prise open his wallet, he's tight as two coats of paint. 

P.S.  I've just read the rest of these posts,   looks like everyone has already said this, ha ha ha. 

* It got written off, you will be relieved to know he didn't throw a seven in the crash, he was fine.  Head on from female lunatic who drove into him while he was stopped at lights and she wanted to cut corners.  I am pleased to report that there were no deaths, despite the Swift not having the same crash test score as a Challenger II.