I hadn’t seen that Waves is diving into the subscription game now. It’s similar to Slate’s Everything Bundle… but you don’t get everything. The downside is that you can only choose 10 plugins, but the upside is that you own all 10 after 24 months. I wish Slate would’ve done something similar. Maybe let you own one after each year.
Anyway, for those wishing to check it out:
https://www.waves.com/bundles/flex
Not sure if the discount would work, but here’s a referal link for an extra 10% off.
Plugin Alliance has a similar setup as does Melda. I would NEVER sign up for a subscription. But a rent-to-own setup is definitely something I would consider. I just don’t like the thought that I have to endless keep paying some company to keep using their plugins. I’d much rather own the software so I could go back to a mix at any point in time regardless of whether or not I’m still paying some company $$. The subscription model makes sense for a company, but not for a consumer - at least this consumer… 
I sure wish Slate would let you own a plug-in for every year you’re on their subscription… Or at least something like that
To me, the rent-to-own model makes the most sense. If you need a plugin for a project and only need it once, you just rent it for a month and pay a few dollars. If you need it all the time, you buy it and spend a bit more. I can’t bring myself to pay for any subscription plugins.