I can't give very good input regarding the 171 but I remember thinking I was bending it in half.
I Iuse a Kessler 168 as my every day board. With an Apex Race V2 plate on it. It can turn short or turn long and is a pretty easy to ride sweet board. It's like a cadillac and ferrari in one! Makes me look/feel a lot better than I am, that's for sure.
To me, this is the perfect set up. Personally I'd never ride without the plate and it doesn't give me any sort of trouble like manoeuvring on cat tracks or low speed issues. The first time I used a plate I was sold and vowed never to go back to life without one. I know everyone doesn't share that same opinion as me. The amount of bumps and ruts the plate absorbs is nothing short of incredible. Perhaps I'm just spoilt.
I might try a custom oxess 164 with an allflex plate at some point in the future as something more aggressive.
In saying that, I ride my powder board (Donek Nomad 164 narrow 21.5 waist) with no plate as that's the ideal powder setup for me anyway. Great for trees, drops, chutes. At 45/35ish angles.