@Cawproductions - I use an iLok 3 dongle, works a like a dream. I always buy outright, never been tempted by subs, as it's a way to lock one into a brand, I like to have the flexibility of 'best of breed' for example the plug I bought the iLok for was the Lexicon native MPX, I actually had the lexicon mpx1 as an outboard unit, but wanted the flexibility of a plugin, so I sold the unit on the Bay and haven't look back, some manufacturers demand an iLok and when they do I'm ready (Eventide for example).
Occasionally a quality brand will have a bonkers sale and I fell more able to fork out for that if I know I'm not going to be paying huge bucks over a few years.
Has no issues, with the iLok, Waves however are a pain in the **** they only allow 1 migration of licenses to a USB stick per year, and then that didn't work particularly well, pretty cheesed off with them, although many of their plugs are really good even though they look a tad old in the tooth, and do tend to hog CPU.
I hOI've stopped my relationship with Waves and moved over to plugin alliance, their stuff is much leaner and re badged UAD so that's good, they have some really good deals from time to time, so I waited and bought what I needed when it came up as a deal, so much better than the subs.
Another reason I don't go for subs is that there is just too much choice, one feels obliged to try one of 20 mastering compressors because you've paid for them, less is more.
Yet another reason would be what happens at the end of your subs, do you lose all the plugs? can you edit old projects with those plugs in?
Also as far as I can remember Slate used to include Scuffham Amps in their Everything deal, but now they don't, so what do you do?
On the plus side from Plugin Alliance is that any new plgin is added to the bundle free of charge, but hey, I have nearly everything I need, and tend to invest now in instrument plugs (just bought the Ampeg VR emuation) rather than EQ's/comps etc.
anyhow, that's it from me....hope it helps