Unfortunately, there are a few dealbreakers with their proposed model that will have me re-evaluating my development environment:
1) Losing the grandfathered pricing if my subscription lapses. I can swallow paying $149/year for the All Products and would do so, but I don't want to feel like a hostage where I'm stuck paying more if I take a month off of using the IDE.
2) $149/year is pretty reasonable, $199/year a little tougher to swallow, $249/year is a no-go.
3) As mentioned, I made a $200 investment in an IntelliJ license with the expectation that I would upgrade each year at $100. Now I'm forced to convert my existing perpetual license into a subscription where I'm held hostage to keep the lower price or I lose access to my product if I cancel the subscription after converting the license.
4) Losing access to the software if my subscription lapses. If the prices were more reasonable (like those of the grandfathered prices, but permanent without the hostage situation) then I could deal with the fact that I need to pay to play. But I feel like we're paying a premium price (albeit for good products). I like the idea others have floated of getting a perpetual license after having paid for a full year subscription.