JTL is mostly easy to use as there is a big knowledge base to explain all functions. We are using JTL-Wawi cloud based by another hosting service (JTL discontinued to offer this service). As we are using a combination of JTL-Wawi, JTL-Shop and some other add-ons and plug-ins, we use the whole system frequently. The customer support is good and helps with any kind of integration, but it is also pretty expensive. If you have the gold service booked, you will receive a professional support by phone though and it can be booked on a monthly basis, which makes it easy to discontinue the service in times you don`t need it. The implementation might be complicated for people who have never done this before, but as it only has to be done once, you usually won`t have to touch the running system.