Its the same. The “coilover” kits generally come pre-assembled, you don’t even need a spring compressor.
Its a huge huge topic, and there are many viewpoints. My views are probably clouded by an excellent conversation I had with Ian Gardiner (IG Racing), who is considerd a bit of a shock absorber guru.
Over the years, on various NA MX5s, I have gone from standard Showa shocks plus crappy PI lowering springs to Bilsteins plus Racing Beat Street springs to Apex’i shocks and matched lowering springs (a sort of revalved GAB (which ended up branded as KYB AGX or Mazdaspeed) to Performance5 Puredrive (Protech shock, Mk2 tops, Pigtail springs) to MeisterR ZetaPro. Along the way dabbled for the very briefest of time with a Racing Gear-Corns setup (it didn’t last long, they were n for about 4 hours before I binned them as a bad idea).
I selected the Puredrives in 2008 on the basis of reviews, knowing Phil Dixon, that they used UK parts combined with Mazda OE parts. They’ve been on for ~100k kms. In that time, I had the usual problems early on with seized damping adjustment (though I think that is less of an issue as some might think; once you settle on a setting, most will never touch it again). A set of rear bumpstops needed replacing, followed by rear shock rebuild (by IG Racing, probably the smashed up rear bumpstops was an indicator of failing rears, and that maybe moving to an effectively NB setup didn’t cure the well known NA rear bumpstop issue).
If I needed replacements, and it was available, Puredrive would have been my choice. They might be a bit old school now, but they suited my needs very well. But Puredrive is no more, and Performance5 is never coming back. And Protech don’t seem that interested.
My conversation with Iain Gardiner was after I purchased the ZetaPros. Originally I approached Protech for a rebuild, but they were only interested in selling me a newer design for a discount, claiming they didn’t have the parts for the older version. Bit of research, and I found IG Racing, who do a lot of Protech setups for stockcars. Interesting; they were happy to rebuild the shocks, using the latest verson parts. I learnt they carried in stock full spares for Protech, GAZ, Spax, Koni, Bilstein, AVO, Ohlins and Penske. I learnt that the vast majority of Japanese shocks could be supported, because they used “industry standard” parts. I was a bit deflated to find that for the Chinese shocks, no such support was possible, as the parts used didn’t follow the norms Iain had found for other brands. I learnt that AVO, GAZ and Protech had a common lineage through Rod Avon, and that the cone design was basically sound. I learnt that where they fail its usually due to contamination of parts during assembly (hence IG would buy these in “dry” and build themselves), and this is generally true of most shocks.
The springs on the ZetaPros went rusty quite quickly, compared to the Puredrive springs. I sold te car, and the next owner suffered spring breakages, wit some worry about whether he could source replacements or not.
Given there is no Performance5, if needed, my attention would probably start with the Tein Street Advance. They seem very fairly priced from an established manufacturer, not a private label shock, where support is always going to be a bit more uncertain. These aren’t rebuildable I think though.
