Naxo footprint and the dead spot question

Search function yields a shitload of Naxo threads, but nothing in this arena:

I bought my girlfriend a pair of Atomic Teledaddys as her dedicated AT ski. El Chupacabra was kind enough to pass on to me his SAC Naxo NX01's, which are size Med.

In the backcountry.com description of the NX01's, the bootsole range supported by the Small was 240-284mm, so I figured my GF would need to Med to accomodate her 286mm Salomon boots.

After cracking open the box and studying the mounting template, it looks like the Small range is actually 240-300mm, putting her 286 close to the upper range, which is desirable, correct? As I understand it, you don't want excess mounting footprint on the ski, for fear that it may restrict the flex.

Her Teledaddy's are 163cm, and this Med Naxo footprint looks mightly long, making the tail appear fairly short. The Medium's will definitely work, but is it optimal?

Questions:
1) Can anyone confirm that the Small supports > 286mm, up to 300mm like the template suggests?

2) Is the extra 3cm of length on the footprint worth worrying about? These skis seem fairly stiff for a 163, and while she is a decent skier I'd like them to perform as intended without being damped too much.

Thanks.

I've pretty much come to the conclusion that I have to have the Smalls, after actually readying the instructions that came with them. No need to answer...let this thread fade into the distance.... Thanks.