Every Garrett powered airplane I ever flew recommended GPU starts if at all possible. They are slow to start without a GPU and if your battery gets questionable, you're asking for a hot start, followed by no start. Can only imagine the big blades on that dude really exacerbate it.
Would have loved to get to try one out once though, just to say I did.
Gotta love TPE's. I drive a five bladed BE100 sometimes and without a GPU starting is truely an adventure. I hear the Cheyenne 4 is a rocket off the runway... supposedly it out climbs Lears initially.
The 400LS could do 3,000 fpm no problem, I think the book climb was around 3200 or 3300.
I thought I recall that Chuck Yeager set some records in the 400 many years ago- not sure exactly what they were for.......