Thank you everyone for your replies, by all means keep posting your thoughts on the various 109's
i would also like to pose another question, do the gondolas significantly effect handling? I've always heard a mix of answers to that one...
Well, they add drag and weight. So yes, it affects handling. In the heavier planes it doesn't effect their fight so long as they stick to the fight they were designed for (read K4 and G-14 here). But in the G-6 and under classes, it takes away half of the fighting capacity before you're even on the runway.
That being said, if you need to get to alt very quickly to tackle an incoming stream of bombers nothing is quite as effective as a 109 loaded for bear with 3 20mm or the 30mm/2 20mm option.
Like I said before, if you want that many 20mm's, go with the 190's. They're better suited to the style of fighting that you'll be forced into anyway.