Just noticed that Splinter Twin and Summer Bloom are still listed as legal in Modern.

I perfect fitted my entire collection.  This however was after 3 or 4 passes to weed out cards that just were not worth keeping.  Now every deck I play is double sleeved, and I never have to worry about finding an inner to add a card to a deck.  My collection is just under 6000 cards.  I had already sleeved anything I played in a deck and just didn't unsleeve them after changing decks, so I needed about 4000 Perfect Fits.  I bought in bulk from a Japanese store, took about a month to get to me, but I paid for 6000 sleeves less than I would have paid to get 3000 from a US distributor, and significantly less than buying packs individually from my LGS or even an online store.

Sleeving everything did take some time, but my wife offered to help, so it wasn't that bad.  Overall I would recommend making sure your collection is as small as you are comfortable with before embarking on something like I did.  I am still actively culling cards, and thinking of dropping all non Modern cards from my collection.  Needless to say this is going to result in a large number of Perfect Fits just floating around my house.