I use the switch version : LXI 11ft6 #7/8. I love the rod because it feels so light in the hand and because overhead casting is nice and easy. BUT it took me some time to accept that the grain window of this rod is lower than what I expected from a 7/8. Best casting results I get with integrated scandi lines around 350 grains combined with trout polyleader. So I tend to consider my rod being a 6/7.
Do not pretend same thing is occurring on their longer spey rods. Maybe worth doing some trial casting before to be certain you get what you're looking for.
I've got the t-pac 12'9 and I find it best with a 600 or 650 skagit, it's a fairly stiff rod in my limited experience...but I've probably only used it half a dozen times so I'm probably not the best person to give a full Run down on the rod.
I have the LPXe 13ft 8/9, for advice on lining it I researched users just as your doing then I asked Guideline via the shop owner.
Result - a perfect set-up, easy loading and casting and I couldnt be happier with it.