Dish washer recommendations?

Looks like my dish washer is on its way out - it's just tripped out my RCD breaker for the second or third time, at the same point in the wash cycle every time. I've cautiously reset it and it carried on without problems, but I no longer trust it.

It's about 15 years old and well out of warranty, anyone got any recommendations for an inexpensive replacement? Just need something basic - my inclination is to get the same Argos model we use at work, which seems pretty reliable, but I'm open to other suggestions.