Had the original SPL Transient Designer (4ch) a long time ago, which was ok, just not my taste, I didn't need it for my production back then, so I sold it.
As for the hardware "cold hifi sound": I have an SPL Kultube that has that, but I actually like it, as a tone. I'd call it analytical, precise. It's perfect for an eightties type disco sound. Sorry @
Karloff70
you know I'm a sucker for bright and shiny.

Never had a Bose system so can't compare.

Put a Telefunken ECC83 and Lundahl transformers in there so now it's slick hifi on a dail. Just like the Elysia Mpressor software, which also has a specific tone. It works great on some drum machine parts, but definitively not on everything. The hardware sounds a bit deeper to my ears, but with the same timbre. I also still have an SPL Charisma with two Philips Miniwatt tubes. It also has a specific tone.
That's why there's a variety of gear? Subtle differences. Different tastes. Right?
As a transient shaper plugin, I bought the Schaack one. The demo convinced me, and it doesn't disappoint.