You're right this one did get shuffled down... I can say a few things, for what they're worth:
I am very familiar with multi-tip systems, but homemade ones. The steelhead guys on this BB will tell you about building hybrid heads using cut-up flylines and cut-up shooting heads to combine both into an integrated "hybrid" WF section or head. The system of switching tips is a popular thing in steelhead circles out west - because every pool has a different personality and water levels fluctuate even in the same pool. The ability to swap densities allows the angler to present even the same fly differently in the same pool the same day.
But that's not what you asked... you asked about SWFF. When I first moved back, I had a wallet full of tips to try on stripers. They worked great, and the ability to switch tips to meet tide flows and depth conditions bought me a lot more fish than if I had been using a single intermediate line. This was particularly true at river mouths when the tide speed changes radically depending on phase.
Although I was having a lot of fun and catching a lot of fish, I had an awakening out on the flats one day. The fish were feeding on sand eels in shallow water. There were fish of all sizes laying on the ripples of sand as the tide ebbed out of the channel that marks this flat's center. Although the smaller fish were suicidal, the larger fish were selective and would often follow without taking the fly. Several fish thicker than fire logs were swimming around out there (30-36" class). The opportunity to hook up with a fair sized fish in a couple of feet of sight-casting water was upon me. I laid the cast out upcurrent and mended like you do in a steelie or salmon river as the current led the fly into position. The fly drifted toward the stations of the large shadows, and the fish got a little antsy as it approached. One shifted over to the fly, but didn't take. I twitched, the fish twitched, but didn't commit. I led, it followed, and then >clunk< >clunk< the loop came to my tip. I was distracted and tried to get the loop thru, but whatever I did really turned the fish off because they both hightailed for the trench.
In steelhead and salmon presentation, you don't strip the head into the guides unless you're moving to the next pool. With a Spey rod, you cover so much linear shoreline with such long lines that you hardly notice the loop unless you're changing to a denser tip.
This is a problem that shooting head guys might face too, whether they admit it or not. Maybe they have engineered a loop that passes thru the guides. I've yet to see something I'd want out on Monomoy on a bright day.
I switched to two spools that day and have never gone back.
This is not to say that exchangable tips are not great, they are. If you want to use them in rivers, they are the cat's meow. If you want to use them for stripers, you just might find you'll have to live with the loops catching in the guides once in a while - and in my case it was just when I didn't want it to!
Hope this gives you one point of view to work from!