I was considering purchasing a few plugins from Waves until I saw a special deal from Slate digital. I did some research and found that some of you felt that you didn't need or use many plugins in addition to what is included in SPLAT, which I have. I haven't heard any plugs demo's so I am kind of in the dark and I appreciate opinions. I know that they are opinions and may differ, but that's what art is all about.

I have some really good outboard gear and subscribe to the theory of getting it right at the source. I am not too much into EDM or synths, mostly do conventional recording of rock, pop, country etc. with good vocals and harmonies.

So my questions are these. Are any of the plugs noticeably better than those in SPLAT. If so, which?

Which, if any, have usefulness that isn't included in Sonar.

Other than a couple of obvious SPLAT plugs, I'm not sure what hardware they are modeled after and how those compare to other plugs so if the SPLAT plugs are good I don't need to duplicate.

I know about Waves, but not as familiar with Slate. How's the quality and support.

If I buy either I will own them, but the Slate Everything deal almost seems too good to be true if they are good quality.

Unfortunately these sales are ending soon, so feel free to answer any other questions I haven't even thought to include. Advice appreciated.

SPLAT offers a lot in the bundle.  Yes, I think there are some "better/different" sounding options from other packages.  But if you can get fully pro-sounding results with what comes with Sonar.
 
What areas do you feel the need to process "in the box" if you are focused on good that the source in your recordings?  I'd say that is the area where you should focus to determine what might be improved and my how much.
 
Waves offers 7 day trials.
 
What is the Slate offer (that includes ownership) that is too good to pass up? I personally haven't seen anything.
 
Izotope is also a major player in the space with some useful tools depending on what you need to accomplish.
 
Noise reduction plugins is something SPLAT lacks.     
 

Slate has an Everything annual least for $149 right now. That's pretty reasonable to try them all for a year to see which ones I really want/use. Mostly I would like to supplement the stock SPLAT mixing tools with complementary ones, rather than replace. I'm mostly old school and want some analog harmonics with digital clarity. Kind of like Steely Dan as a reference. Right now I don't care too much about mastering, although that could change.

I like the rich lush Reverbs sounds, like Lexicon. If the 480 emulation from Slate is close to the original that would be big. I don't think that SPLAT has anything similar.

Thought about an 1176, but only if it is better or different than the stock SPLAT version. The SL package from Waves looks good. Is the Waves CLA2A better than the SPLAT version. The AP 2500 also looks good.

Like I said I have lots of questions and I'm looking for suggestions.

Steely Dan didn't have any plugins from Waves, Slate, Fabfilter or iZotope. They managed.

bitflipper
Steely Dan didn't have any plugins from Waves, Slate, Fabfilter or iZotope. They managed.

Do you know that for a fact? 
I wonder if they ever used Sonar too? Please tell us.

I did a mix using Sonar Prochannel only. Then I did the same mix with only Slate plug ins. Night and day. Slate plug ins for me sounded far above anything I used in Sonar. Softube makes really good stuff too, and I believe they also have a subscription service.

pathos

bitflipper
Steely Dan didn't have any plugins from Waves, Slate, Fabfilter or iZotope. They managed.

Do you know that for a fact? 
I wonder if they ever used Sonar too? Please tell us.

When Steely Dan was in it's prime, they didn't have computers outside of big business and the Govt.

ampfixer

pathos

bitflipper
Steely Dan didn't have any plugins from Waves, Slate, Fabfilter or iZotope. They managed.

Do you know that for a fact? 
I wonder if they ever used Sonar too? Please tell us.

When Steely Dan was in it's prime, they didn't have computers outside of big business and the Govt.

So what?
When the tech came along they did. They worked with Pro Tools on later releases, maybe not exclusively but they were familiar with it.

bitflipper
Steely Dan didn't have any plugins from Waves, Slate, Fabfilter or iZotope. They managed.

Yeah, Steely Dan didn't need no fancy pants plugins. They made do with hundreds of thousands of dollars worth of state of the art hardware, the most talented and experienced musicians and engineers in the business and virtually limitless studio time. 

I am really enjoying the Neutron plug in from Isotope. Also Ozone 7 Elements. Plenty of vids on YouTube showing then in action.