I have had problems with a few Maxell SVHS tapes in my PVHD1000 in the past but as of this date, not a problem with any SVHS tape I have tried on the Mits. I bought a bunch of Maxell ST180's recently and just recorded Harry Potter plus the previews of the new HP movie that HBO aired. It recorded fine without a single dropout on the Mits. I don't use this tape in the Panny because it has had sporadic issues of the dreadded green blotching. I must have gotten very lucky with this Mits. I have not cleaned the heads since I got it. I did do a routine wet cleaning when I first brought it in here since I actually got this one used.
My all time favorite SVHS tape for DVHS recording is Fujii brand, the cheapest I can get. The only true DVHS tape I use at all is the JVC DF420 and then only when I want to record for more than 3 hours at a time.