Hello,
Would you recommend a festool plunge saw for precutting exceptionally crowned stock for the planer?
Nope.
A thousand and one other reasons, yes- just not that specific one.
The TS55EQ/TS75EQ's really shine on sheet goods and specialty cuts where the plunge feature is required.
It's outstanding dust control also makes it ideal for use "on site" - where "on site" may happen to be the living room and/or kitchen of an expensive house.
From the sound of things you may have in mind, you might want to look at the EZ forum here. The two systems (three if you toss in the DeWalt) really only converge where they use a rail system to semi capture a saw.
Other than that, the systems all deviate from each other in the details & specialty applications.
"Life is what happens to you while you're busy making other plans." - John Lennon