Petrel is pretty solid, just for comparison have a look at the HW otsc.
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Allow me to paraphrase how these computer threads usually go:
"I think the computer I just spent $1500 on is the best, because of <insert justification here>."
...the same seems to happen with the what scooter should I buy threads, too.
I was on a boat last weekend where there were 3 Predator divers and 3 X1 diver. All X1 divers had returned their unit for service or replacement. One unit had been replaced 3 times!!
Predators were all yet to need customer service. That says volumes....