I have used the Seedhouse SL1 for my entire PCT Thru-hike this summer and I have found that you really only need 6 stakes:
2 for back side corners, 2 for mid-side guylines, 2 for front vestibule corners.
Staking the back center corner is redundant with two other stakes so close buy. Ditto for the front corners of the tent if the vestibule is staked. I have been in some strong winds numerous times, I would guess 40+ mph, and nights of continuous rain in Oregon. I would think that six stakes would also be enough for the Fly Creek and the original seedhouse 1 (not SL).
I haven't used the Fly Creek UL1, but I am thinking of switching to it to shed some weight for future trips. I am only 5'6", so I am not too worried about the slightly smaller size. I am wondering if anybody has had condensation issues with the added non-mesh sides or if the ventilation is still adequate with the fly on? And also, if anybody has used both the Seedhouse SL1 and the Fly Creek UL1, is the Fly Creek any warmer due to the higher non-mesh side-walls? This could be a bonus for shoulder season.