I love my E30, for it's fast handling, loads of features, and IQ.
I love my EP1, for it's handy size, it's great jpegs, and it's IQ.
But if I could only have ONE camera, I would select neither one.
The EP1 reminded me about how much I like having a smaller camera, and the E30 features are hard to give up. So I would take an E620 with a 14-54mm lens.
The E620 is pretty much a "mini E30" which is just missing the great OVF of the E30 and is much, much smaller and lighter.
I really loved my 14-42mm lens on my E510, but once I got a 14-54mm lens, there is no going back. This is perhaps the finest kit lens made by anyone. Period.
The 12-60mm is an awesome lens, but I just feel it is too large and heavy for a small camera like the E620.
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