My personal opinion of Manic is not high: I find him boring and rather sanctimonious. I know that Manic has a low opinion of your humble Devil, because we had our own little bout of online fisticuffs some time ago. I haven't bothered reading him since (not that I did very much previously. On the grounds that he's a bore). Although I do support his campaign to get Private Eye to put its "serious" bits online.
Guido I find relatively entertaining but, frankly, a little too obscure; I am not part of the Westminster Village and I find much of his output rather too oblique. I tend to pop in occasionally but, if one really doesn't know to whom Guido is referring when he drops his hints, the entertainment is, necessarily, limited.
So, who do I support? Well... No, sorry, I simply cannot summon up the interest to go for either frankly. Guido will continue to write his gossip, and Manic will continue to campaign earnestly in Parliament Square and I wouldn't have thought that either of them could give a two shits what your humble Devil might think in any case.
I'll stick to reading my assorted favourites. You'll find 'em in the sidebar: why not have a scout around whilst I'm sunning myself in the