How badly do you want to make the switch? I speak anecdoatally here when I say that late 90's Camrys are not the best that Toyota produced. Another thing to consider is that Toyotas and Honda are generally no more reliable than their counterparts. Over the years Toyota and Honda have gained perceived reliability - most models have suffered from problems just as any other car but large production volumes and maintaining the model name over decades has driven down the average repair trip per car.
All that being said, this is the only criteria I would use to evaluate the two mechanically (assuming rust and cosmetic things are a non-issue to you). The 4cyl Camry has a non-interference engine - if the timing belt breaks (the number one thing you need to worry about as a car ages), the valves in the engine will not smash into the piston heads and destroy the engine. Your Hyundai has an interference engine, so that is an outside possibility.
The chances of the timing belt breaking are slim, especially if you have it replaced at the correct interval. Is the fear of thousands in engine damage enough to get you to go through the buying and selling process? If yes - do it. If no - don't bother.
