Well I called Isspro today in Portland @ 503-288-4488& talked to Don about my gauges. He said on my pyro #R607 that sitting at 75*-100* at start up probably be OK, but sitting at 200* or so would not be good.
My Boost gauge #R56116 showing 1# probably was getting gummed up & sticking, if it was going ahead & climbing as my boost increased then it probably be ok, unless it just wasn't working at all.
I told him when my gauges were installed, ('90) how long I have been using them. He told me that I'd probably got my money's worth out of them. He then quoted me $126.19 for another R607 pyro gauge & $55.29 for another R5611R Boost gauge.
Maybe I didn't say things right to get much help. I just told him outright how long I'd used them & how they were currently doing etc. I did tell him I had the TTM #R4130 cool down monitor & was pleased with it.