If you get an MPX, you will end-up selling it. It's not that great of a unit, even if you get later updated model. Sub-par effects, preset switching lag, intermittent rebooting... If you get the Lexicon switcher, plan on replacing every switch in the board. I've been there, and it's a PITA!
I don't get this obession with "transparent" guitar effects? The singular aspect that makes the EP1/2/3 tape echo, Roland tape echo, DM-2 delay, CE-1 chorus, Uni-Vibe, Leslie speaker cabinet, etc... sound so great, is the fact that they add a certain level of coloration. Lexicon knew this, which is why they designed the early units with coloration. Transparency (IMO) is best suited for vocals, and acoustic instrumentation.
If I may...
Per my experiance; those who began playing in the era of digital racks and effects loops exist in an alternate reality. Back in the day, building a "tone" was an additive/subtractive process, using a multitude of various devices. Robert Fripp, Jimi Hendrix, David Gilmour, Robin Trower, Jeff Beck, Jimmy Page, Pat Travers, Alex Lifeson, Ted Nugent, Edward Van Halen, Randy Rhoads... were all pioneers of the process. Compare Alex Lifeson's 1st RUSH album tones to his later "rack" tones... Not even close!
Someone recently posted a clip of his band. To my ears, it sounded like every other band I've heard in the last 20 or so years. Not that it wasn't good... it just lacks originality. The "worship" bands all sound like U2! The most impressed I've been in a long time, is with the guy who plays guitar in Greta Van Fleet.