We don't take very much with us either as we charge everything back to the room and subsequently to our US$ Mastercard. Most trips we have no more than $500 and ususally come back with $200 or more. If for some reason we need more cash, I just use an ATM and gladly pay the $2 or $3 fee because of a bad experience a few years ago.
I will never use travellers' cheques again. On a trip about 7 years ago, we had taken American Express travellers' cheques with us and had some in the vehicle as we drove to WDW. Once we arrived, we forgot they were in the glove box and they ended up being stolen while we were parked at EPCOT. We notified Disney Security and then filed a police report with an Orange County sheriff's deputy. At that time, American Express was an official sponser of WDW and had an office at the Contempory Resort. We headed over there to make a claim and it was downhill from there.
I won't go into a lot of details, and it wasn't a large sum of money ($600), but it took us 3 days and multiple trips per day to the CR before they refunded the travellors' cheques. The service they show on their television ads is not how it worked out for us. The American Express agents were rude and demeaning to the point that my wife became so upset, she was in tears. A very nice Contempory CM intervened on our behalf and helped the process along. We had everything we needed (copies of the serial numbers, police report) but I think the problem was that the cheques had already been cashed. As everyone knows, Disney Cast Members very rarely, if ever, validate a signature... whethere on a travellers' cheque or when using a credit card.
Anyway, that was our experience and maybe for others who have had TC lost/stolen, their experience was more positive, but because of it, I'll use an ATM if I need cash.