seals work rather well on the journal-bearing turbos.
You also have a LOT more flexibility with design when it comes to using journal bearing turbochargers. You can mix and match turbine and compressor wheels that aren't available in ballbearing format. An example: there isn't a 76-trim 10-blade 28-series turbine available in a ballbearing format but you can find it in both 10-blade and 9-blade variations for journal bearing designs. If you want to install a different compressor wheel onto a ballbearing cartridge/turbine, you are going to be limited in your choices as you will not be able to machine the front flange of the housing to accept a slightly larger diameter wheel (exducer side).Additionally, no one sells parts for ballbearing turbos as they cannot be rebuilt - they are in essence, a throw-away turbocharger when it comes to maintenance. Journal bearing turbochargers, when properly built-up using high-performance components (such as 360-degree thrust groups and carbon shaft seals), will offer notably better reliability - near if not the same as a ballbearing design. Most ballbearing CHRA's are around $750 each where you can rebuild a pair of journal bearing turbochargers for just a little more than that in most cases. In the end, neither one or the other is obsolete - they both have unique attributes. p.s. Ballbearing turbos have thrust loads too which are handled by the bearings. :)
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