I thought about doing the same thing, especially with the intro pricing on the 2EX. But I figured it could be a fun project and a way to learn, since I had never done an upgrade before.

I bought the S1 12 years ago now (they had just launched). I skipped the NRT upgrade and heard that early cabinets didn't do well with the S2 upgrade. So I sent my S1 into Ascend... and they were unable to upgrade the cabinets. So I'm glad I didn't try myself! Ascend sold me new cabinets at cost and I got brand new S2 speakers with a fresh warranty about 4 years ago.

So I debated it too and honestly it would cost you roughly the same and as a bonus someone else gets a set of amazing speakers! I didn't get any takers from friends for the S2 so I went ahead and ordered the upgrade kits. I just completed my S2 -> S2EX upgrade for 3 speakers (LCR). Not sure yet what to do with my spare parts.

They're breaking in and then I'll need to redo calibration, but I'm already loving the additional clarity and punch/dynamics!