Line blend skis

i dont think you should, and im of the opinion that "if you have to ask, no you shouldn't." i say that because dead center mounting is something you only should do if you are a 100% park rat or just love the way it makes your skis feel, and in those cases you know it. otherwise youre getting the downsides of a center mount without knowing it's worth it for you

if you dont know much about it, just go recommended. line especially has "progressive" mount points, it's not like the old days where you had to worry about the recommended mount point being way the hell back on the ski

make sense?

If you are skiing nothing but rails, center mounting will maximize performance on them but sacrifice performance on everything else. You will get more pop off jumps and stability moving back 2 cm and even better carving/all mountain performance further back still. As a quick guideline on most directional twin tip skis:

Center Mount- Best rail performance but sacrifice in other areas.
-1cm Back of Center- Good mix of rail and jump performance.
-2cm Back of Center- More stable at speed and better pop off jumps but sacrificing rail performance as it's not as quick to pivot.
-3cm to -4 Back of Center- Even more stable at speed, better carving capabilities while still decent in the park.(50/50 park and All Mountain)
-5cm to -6cm Back of Center- All Mountain mounting point of most twin tips. Stable at speed with great carving ability but not as easy to pivot or throw around in the air.(Mostly using outside of the Park)

Line Blend has a "Factory Mounting Point" is -3cm back of center which would be good mix of All Mountain and Park use on the line. If you ski more park, move closer to center or if you never ski park, move them back a bit for better stability. The ski is marketed as a "The whole hill is your park" type of ski and the factory line would be a solid recommendation there.

centre those puppies

Line reeeeally wants you to mount their skis at recommended, based on conversations I have had with their tech department. This has kind of been said already, but I imagine the reason they push it so hard is that anyone asking probably doesnt really know what they want. What they probably want is a ski that skis really well and can sometimes go rip the park. If brand were not as adamant about telling people to mount at recommended, more people would likely mount center. And then many people will complain that their skis dont perform well on "normal" slopes. That is my theory at least.

tldr: If you are a park skier who takes the occasional "other run" lap, center will treat you fine. If you ski everywhere, including the park, equally, recommended is probably the way to go.

I have blends and actually had them like -2.5cm and I switched to center because I moved more towards park in the past season. I absolutely like them better now on rails which is what I wanted but they are more washy when skiing fast (they don’t want to stay in a straight line as much). I don’t mind having to control the ski a little more, but you will have noticeably better stability at high speeds if you mount 2 or 3cm back. Mount them -1 if you’re looking for an in between or at recommended if you don’t care about park and want them to be stable at speed, float really well in pow, and turn on a dime.
So:
Center for hardcore park performance
-2 or -3cm for a good park/all mountain mix
Recommended for best all mountain performance and float