Hi Ardy,
I have purchased the E410. I've been going through the same struggle trying to find a good 1:1 macro. Here's what I've learned from Tropical1 (Phil Rudin) and others who say the same thing.
Macro - Best to buy the 50mm macro lens and the port. You can screw wet diopters to the front 67mm threads if you like. You can also add a teleconverter 1.4 or 2.0 that will increase its macro ability. If I were starting all over again I would buy the lens and the Inon Port with the magnetic manual focus rings. Most people that I see usually have a macro port and a dome port.
Here are some alternatives I ran into during my search that appealed more to me based on my pocket book, the need to purchase another Inon Z240 and the fact I already owned the 14-42 port and lens.
1. Buy the 50mm macro lens, use it in the 14-42 Port. It'll work in the port so this is the route I've chose to go.
A. You can add a wet diopter to the front of the port and here are the ways you can do it.
a. Woody's diopter..simply cut your port cover for the PPO-E05 and slide the diopter in the opening. Currently the diopter only comes in sizes too small to cover the Oly port but I have it from a reputable source that you can do this. My only worry here is keeping it in place and storage when its not attached.
b. You can use an Inon or Athena setup which basically puts a 67mm mount on a small arm you can move in front of the port when you need to. This seems a lot more stable than option A but the setups also cost about triple of option A.
I'm pretty much set on giving the Woody's Diopter a go. I've never been one to shy away from experimentation.
The E-420 is intriguing and due to the fact that it is the same size of the E-410 a housing should be easy to make. There's a preview on fourthirdsphoto.com The ingriguing part is will have the same sensor as the E3 and live view might be a tad faster...but still not as fast as the E-330.
PS..if you're interested in the range of the 14-42 I've taken some photos here, nothing good, but it does show the range of the lens.
http://www.scubaboard.com/gallery/showgall...cat/2785/page/2