Once I determined that the light meter in the camera was unreliable for setting these, I've become adept at using the Lux Professional Light Meter app for iOS. This is a great app, by the way. It lets you determine readings based on ISO, f-stop and shutter speed.
Here are a few of the recent pictures that I've taken recently with this lens:
Reviews that I've read about this lens say that it also makes a pretty decent prime lens for regular photography as well as macro. I haven't tried it for this yet.
I got this lens very cheaply with the idea that I would play around with it for a while and then sell it on eBay. Now I'm thinking that this is something that I'd rather hang on to.