Pressure vacuum test. I doubt it would gernade. So build you one and take the surprise out of it. I have about 650$ in my 660 kits. I think these blue ones will last a while, cut good. For a little effort you can make a kit last year's. Here you could not find a used 660 for less than 800$ if you could find one.Dunno what you mean about testing them. I only really test stuff dealers I know in the UK send me to test since I do deal some of their items. For me, it's more about whether it is worth it to give it a try without it grenading so much as to destroy itself and be a total loss. I think you've answered that question. It's not really worth it even at the price, is it? I mean, unless it's a toy. I don't need a toy. I'll look more towards a used 660. Which of course, is also a gamble as well...
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