Have to say first that I have always been and still am a big Panasonic fan - TV's, DVD players, VCR's, alarm clocks, video camera's - I've never had a problem with any of them and they're all Panasonic! However I have had problems with their microwave ovens, perhaps it's only this model, but I've had x2 of them now after returns from different suppliers, both exhibited similar issues.
Comes down to them resetting themselves a lot, you'd be half-way through a cooking cycle and it would just stop and reset itself with the display "refer to operating instructions" as if it had a power cut. Additionally with this latest one I purchased, the count-down timer would suddenly freeze but the cooker still continued - that is plain dangerous! So I've sent this one back for a refund and will purchase a different model altogether.
Don't let this put you off buying Panasonic equipment because I still think they're great, I just wouldn't recommend this particular device. If you do decide to buy it - keep the receipt just in case!!