I've tried a few other processors in my 9 years in business. Total Merchant Services is the least expensive. I filled out the app online and my machine was delivered to my business preprogrammed and ready to plug in.
I decided I would attempt taking credit cards via my Smart Phone. Total Merchant Services sent me a FREE card reader for my Smart Phone so I could do business at a new comic convention.
I have had disputes with customers from time to time while taking credit cards. At least with Total Merchant Services my disputes were settled effortlessly so I could get back to work.
I own a restaurant and recently started using the FREE Fanminder Service from Total Merchant Services. My business has increased by 10% by allowing me to send coupons to my customers.