The GT3582R pictured is the common non-ported shroud (which has an optional ported shroud), compared to the GTX which only comes with the ported shroud.
Garrett Provides this info:
Turbo______ Inducer____Exducer___Trim __AR
GT3582R_____ 61.4mm____ 82.0mm____ 56___ 0.70
GTX3582R____ 62.5mm____ 82.5mm____ 58___ 0.70
Again they don't mention the extended tip size, but the GTX3582R measures 84.7mm, which is 2.2mm bigger than claimed.
Looking at the compressor maps you can see, just like the other turbos that now customers thinking of doing a GT4088R, now might consider the GTX3582R. Its almost 100 engine HP more than the old one! Again it all depends on when it spools up.
The full 11 blade compressor wheel is very nice looking, but does it work is the question! Garretts info says:
Forged, fully-machined compressor wheel featuring next-generation GTX aerodynamics * Compressor wheel is 11 full-blade design.
As i mentioned before they say nothing about the extended tips! You can see above the side profile showing the tips and how they protrude out from the wheel.
I know this is not proven power, but look for results very soon!