I owned and run:
Soon to perhaps get another GTB 3.5R!!
THe early models were prone to funny thermal problems, a few strange sensor harness problems and the weak magnets. Some had fet issues.
That said - All of mine have performed flawlessly.
Locally - most guys run Novak. Says something..
A guy bought a GM and is having issues with it. BUt GM service is crap.
There are one or two Nosram and LRP systems running here. But mainly Novak.
I think Novak sometimes gets a bad rep, if only because they have a good deal of the market(At least locally they do!). They're the only problems and failures advertised!
That said - if there's one thing only that makes you buy Novak...
Novak customer service is legendary. Fantastic to deal with.
That's enough for me..
(Incidentally - I have a bunch of Futaba, and ran Nosram too.. So it's not like I'm Novak obsessed..)