I wanted a work watch to abuse through the summer, I liked the looks of the 218 but thought it would look better with a negative display. It is a very easy mod, just a module and band swap. I went about getting the parts and ordered a W218H-4B2V and a B650WB-1BVT. When I received them I noticed that they have different module numbers....I never thought to check since they look identical. I proceed with the swap anyways and they are completely interchangeable with perfect fit.
The only difference I can notice is that the 218 module 3224 has slightly smaller digits for the time but has slightly larger digits for the day and date where as the 650 module 3454 has slightly larger digits for the time and slightly smaller digits for day and date. You can't even tell the difference with a quick glance seems strange for Casio to bother with the display differences at all. The band is from a SGW-450 I had lying around and wasn't going to use the original orange band that came on the 218 since I was going for a more stealthy look. I am aware of rating differences on bezel and band and will eventually remove text from both in the future.
It is super light, very easy to read with good contrast in most lighting and has a very good backlight, a perfect beater work watch.