I would certainly suggest the e2 over the e1 unless space is at a absolute premium and you don't think you would carry the E2 being it's about 1" longer.
The E2 (60 lumens) is 4X as bright as the E1 (15 lumens) and after owning a few surefires the only reason I can think of owning a 3P/E1 is if you knew the only reason you'd use it is it's very small and a slightly larger light just will not work. I still get depressed every time I use my 3P, it's just so Dim compared to my other surefires. I know a lot of guys like the E1 but just understand that you are giving up a TON of light for the smaller package. Rumor has it they are looking into a 30 lumen bulb for the E1/3P but I'm not sure how that would effect runtimes, and still.....maybe I just have really big pockets but I'll take 4X the light for a extra 1" of flashlight anyday. The E1 does have a slightly longer runtime at 90 minutes so that is a concideration. I hope someone can post a comparison from the e1 to the e2 because after seeing that I think it will easily make your mind up for you.
The E2 looks very promising, 60 lumens of light is super bright and 75 minutes of runtime in that small of a package is quite a deal. It's definatly the one that has caught my eye of the new lights.
If price is a big issue the G2 runs about $45 shipped and runs 65 lumens for a hour, there are a lot of reports I've read hinting these new polymer lights may be the most durable surefire has produced yet. The G2 is even a little larger yet than the E2.
Another light that maybe the best bang for the $ is the 8NX commander, polymer rechargeable lights. 110 lumens, 50 minute runtimes, 2 batteries, ac/dc charger, light for around $90 shipped. It might be larger than what you'd want to carry everyday but I'd say that's certainly the most bang for the $ in their lineup with the G2. It's a good sized light, but if you use your light a LOT those little $4/cell lithium batteries can add up quickly.
If I was knew into surefires and didn't already have a 6p,9p,9N, 3p The two I'd be looking at would be a E2 with a 8XN for that would be a hard combo to beat for light output and cost.
Todd