The client not king in the battery business

In the battery business... My relative young 652 battery packed up within 18 months. Which is too short a period in my humble opinion. So I did my homework and found: 1. None of the battery websites in SA list my 2004 VW Passat TDI 96kW model - they all refer one back to the petrol model and then advise a 652. Now those in the know do know that a diesel needs higher capacity and higher cranking values in the battery than petrol equivalents. 2. So I did some international research and came to the conclusion that one needs a 80Ah with at least 700A cold cranking capacity, available in sizes H7//L4/LN4/Gr94R for the vehicle. Some more research revealed the 668 would fit the bill perfectly. 3. Went to the first shop, but no stock of the Duracell 668, my first choice. Could get it later the day, but as my car no longer was able to start on the old battery, it would be risky to try to come back later. No stock, no sale... 4. Went to my second choice, a Willard shop. Told them I want a 668 for my Passat TDI. They had stock, even 2 of them. But between the manager and his 3 assistants they tried to convince me: a. the battery won't fit as the space available is too small; b. as the battery is not listed on their system as suitable for my vehicle they can't honour the warrantee; c. The 652 is the correct model, and if I want a bit more sturdyness they can fit the 652 AGM model or perhaps the 658, but not the 668; d. They know these Passat diesels very well, and they always fit the 652. It took me about 20 minutes to convince them to at least try to fit the 668 in the space available. Which they did in the end, and surprise: it did fit! And it works well! So herewith my request to the battery guys: 1) Please add the VW TDI's to your system (although after the Dieselgate there are not many new ones, but quite a lot of them are still running around) with the correct battery versions for diesels: In the case of the 2001 - 2004 Passat TDI (B5.5 or 3B3) the 668, and 2) listen to the client who has done his homework, don't fight him. Fighting the client doesn't help to create confidence.