The Ace was my main amp for a few years until I switched to the Mark V. The only reason I sold the Stiletto was to fund the V. Were I a wealthier guy I would definitely still have it.
Never wanted more clean headroom with that amp, honestly. If you want sparkly clean and Recto-style distortion, none of the Stiletto's will suit you. If you want a chimey, throaty clean and a searing, snarling lead tone, the Ace is perfect. There's something magic about the Ace - I've tried a Deuce version 2 as well, and it just didn't have that same feel, even in 50W mode. I think the OT is different on the Ace.
If I had kept the Ace, I would have used it as my lead tone amp; it really cuts and sounds fantastic on tape for solos. It's an excellent amp if you're in a band with another guitarist, especially someone who uses a Recto/6L6 style of amp.
If resale value is a concern, the difference on the used market seems to be small (usually $100 less for an Ace). I sold mine last year for $1000.