301 redirecting to boost sites

I have 3 sites each for a different hotel which we run as one business in close proximity to each other. They're all PR3, target the same keywords and currently are not interlinked. They're all strictly white hat and rank pretty much equally on p2/3 of Google.

There's little benefit in keeping the 3 seperate other than they can have their own identity for the punters so I'm wondering if there's any justification in 301 redirecting them all to one 'master site' in the hope that this single site then gets an healthy leg up the SERPs from the 3 sites worth of Google juice?

Anyone able to offer me any advice on this before I bring the whole empire crashing down in spectacular fashion?

I would just keep in mind that if these sites link SOLEY to your uber site, they might then be seen as doorway pages. Get around that and you will have an indexed site with at least 3 good PR backlinks. Might not be worth the risk or the hassle.

So what you're saying is I'd acheive practically the same result by simply linking them together (albeit only 2 links each)?