Im sort of in the same boat but not with Reefs2Go.

Champion Lighting and supply is where I bought my salinity probe from Digital Aquatics along with the SL2 module. Everything shows instock. Eighty dollars for the module and 90 for the probe. The module came in, but no probe. Its been 2.5 months and 6 inquiries later after being told they expected them in every 2-4 weeks, I now find out that DA pulled all of their probes because of problems and havn't issued anything new. I was charged for both items and had to call them just last week to have them credit my card. So technically I paid for something and never got it. But they were nice enough to credit it as they finally admitted they have no idea when there going to get them back in stock.

Right now, im sitting on an 80 dollar module and have nothing to use it with.