It is tough to make a descision on who to use. I will tell you alot of your customers have a preference. I switched from Coke to Pepsi about 3 years ago based on Coke's problem with customer service in my area. I still keep 6 packs of coke behind the bar for customers who are adament about needing a Coke.
It wasn't until I switched that I noticed my customers having a preference. I live in Texas and here they call everything a Coke. (Pepsi, Sprite and Dr. Pepper are all known as Coke) I noticed that many customers were glad we had Pepsi instead of Coke. Also vis-a-versa. I was shocked to see that my my number for Coke/Pepsi drinkers stayed the same. It wasn't that big of change for most. I seen about a 30% increase in my Diet Pepsi sales. Turns out many people prefer the taste of Diet Pepsi to Diet Coke. I saw a little slip in Sprite drinkers now having to drink Sierra Mist but nothing major. I carried Dr.Pepper with both comapnies. I recently added Diet Dr.Pepper to the line up and the results were rather shocking as well. Enough about that.
The big change for me was service and price. My cost on BIB went down $9.50 per 5gal. box and I get more from a 5 gal. box than with coke. Less ordering. Also Pepsi gave me several coolers and refridge units to keep products cold. Tons of table tents and signage were available but I declined to take them. Also we get a check cut every quarter for $1500 at each of 2 locations. The Pepsi rep comes by and has lunch at least once a week. While here he also checks up on me. My area is known for bad tasting water and Pepsi offered to put in a water filtration system to help the quality. After 2 years of asking Coke for this they refused. Pepsi even changes the filters every 4 months without me calling and asking them. My order are sent from somewhere else but the local company keeps a good amount on hand incase I ever slip up the order. My overall saving was about 17% without figuring in the rebate.
In my opinion I would go with a company that provided great service. If you are using a fountain system it is often tough on how to tell the difference between each product. Especially when water quality comes into play.
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