W Trek

I have been having difficulty booking my own campsites for the week of December 26th through Jan. 4th. I have found a W trek expedition through Erratic Rock that leaves that week and one through Fantastico Sur. Does anyone have information about these treks and if one company is preferred over the other. Coming from the U.S where everything is booked with credit card, I am a little concerned about payment being a direct deposit into the bank account of Erratic Rock as my only form of payment. Can anyone ease my fears on the company and the form of payment? I think I would go with Erratic Rock if I wasn't so fearful of this form of payment. Thanks in advance.