"Different strokes for different folks."
Dav, the DeWalt switch isn't a bad switch, well not any worse than ANY switch. It is just that it will get saw dust in it and cause the contacts not to contact.
The foot (dead man) switch just make things alot handier and easier to use. By repacing the orginal switch with a "wall" style hasn't helped you at all. It has just temporaly moved the problem to another place. You still have to take one hand off your work and fumble around to turn the saw off.
If you sit on a tall stool, just mount the foot switch to a "block of wood", "a box" (of the correct height) or a "platform".
It will take you about 15 minutes of getting used to it, and then you will be a very "happy camper" (well scroll saw user) in this case.
In fact, I have a "kill" switch on my table saw that I can bump with my knee to shut the power off with out moving a hand or loosing controll of the material I am cutting.
Cost is a problem, (I payed $40.00 for my foot switch) but, as others have said, you can get one for as little as $10.00. It will be a very good investment to your hobby.
Rog