For many years we only bought electrical supplies from Glantz, mainly because the other suppliers didn't have as good customer service. They closed their local branch and Pioneer is just a ten minute ride up the road. They are pretty good, but I do have an issue with Pioneer for transformer and ballast returns. When you return a transformer/ballast they don't give you credit right away. It can take anywhere from a couple of weeks to a couple of months for the credit to appear. In other words, if you take out a trans and bring it to them for replacement you have to buy the new unit and a credit will show up later. Also, they don't issue a credit memo right way, you have to keep track of it yourself. Now that could be due to my office not handling the paperwork properly. My secretary does that because I am already spread too thin (though not my waistline) to do everything. For other returns they are really good.
I haven't used Glantz much in the past year or two (they don't have a branch that is less than 90 minutes away), but they used to have a pretty liberal return/credit policy on transformers/ballasts. I'd call them and see what it's like anymore. Also Glantz carries more brands than Pioneer. I.E. Pioneer doesn't (or the last time I called didn't) carry Transco transformers.