VDO 30-0-25 PSI
Pros: Cheap (~$45), shows vaccum
Cons: dim backlight (better than 0-30 though), too deep for standard Miata a-pillar, boost numbers are really close together.
SPI 30-0-30 PSI
Pros: Nice construction, good layout, choice of face colors
Cons: Expensive (~$125), too deep for Miata a-pillar.
Autometer 30-0-30 PSI
Pros: Nice construction, nice number layout, fits in Miata cup.
Cons: More expensive (~$80), only in white face.
HKS early model 30-0-20 PSI (Pictured installed in Franks Miata)
Pros: good construction, no flickering of needle, decent lighting, shallow
so it fits the BEGI cup.
Cons: Expensive, only goes to 20 PSI and I was running higher boost (not Miata), and I don't think they're available in PSI anymore, only bar
I'm negative biased towards this gauge right now because the one I got from
Corky wasn't centered on Zero and had problems. He's replacing it now but
I'll give my opinions on what I've seen so far.
Pros: Cheap (comes with BEGI turbos), available from JC Whitney, nice
widespread boost numbers, fits in Miata cup.
Cons: available from JC Whitney, cheap construction, very dim light, needle flutters when not in boost (could be source related)