i currently own a bibler firstlight, i initially purchased the lighthouse, but decided to exchange it for the smaller model for several reasons.
the catalyst was that the velcro that secured the poles inside the tent had poked a pinprick sized hole in the tent fabric, the folks at bibler were absolutely flabbergasted by this & in my replacement tent (the firstlight) the velcro tabs were much cleaner cut & i think it'd be unlikely for any holes happening, i'm guessing it was just a fluke that the velcro tabs were cut badly in the first tent. however/also, in the course of regular setting up/taking down of the lighthouse short, top pole that holds the awnings out must've also pinched the tent fabric & produced another pinprick sized hole. ouch. nonethless bibler was awesome about replacing the tent.
despite all this i'm a big fan of epic fabric, having had a sleeping bag & 4 jackets made of the stuff.
so, i capitalized on the holes in the lighthouse to exchange it for a firstlight, because simply, the lighthouse is *way too big*, unless you're *always* going to be camping with 2people, go with the firstlight, you can leave the vestibule at home when you're going solo & bring it along when you're doubling up, & still have plenty of room either way. this seems to offer the greatest combination of weight savings & versatility if deciding between the two models.
what might not be considered when comparing the square footage of the 2 tents floorplans to other makes'n'models of tents, is that the walls rise very steeply, giving you a greater amount of useable space per square foot than other designs.
also (maybe other readers can comment on this) i found the angle at which one had to insert the poles into the lighthouse made for a smidgen more difficulty setting up than i wanted to deal with, not a huge deal, but with the firstlight the poles are inserted lengthwise & it's easier to get them flexed into position than with the lighthouse.
i've since lent my firstlight out to a friend who treats gear incredibly badly & it returned unscathed, after a 2wk trip.
the tent has held in line with my experiences of epic fabrics weather worthiness in general, i think it's a great material, but can require some psychological adjustment, in that with garments & with the tent, the fabric can feel wet to the touch, but still not be permitting water to get through.