Stating the obvious doesn't make you point more than what it is...
I'm a visualiser with 7 years experience, I've built two i7 rigs both on quadros (3700 & 4000), I've also owned computers and upgraded them with gaming cards. It makes little sense to use one for the other when they are designed, managed and updated for what the supposed to be for. Call me mental for that if you like.
Personally I've have worked on crazy scenes containing multiple 100s of millions polys containing anything from proxys to nurbs, a gaming card would fall apart dealing with viewport swift command arch rotates and general maneuverability there. I like to be in a position to be able to cope with whatever comes along in my work. That makes sense to me.
Well OK, if that's how you feel then you should probably carry on using those quadros, as I said it's just my opinion

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I can tell you though, my gaming card doesn't fall apart dealing with multi million polygon scenes, even with shadows ambient occlusion and advanced transparency enabled in the viewport, I admit that this one wasn't cheap (690) but the last two (580 & 480 and the 275 before that) have all performed just fine.
Back before I stopped with the quadros I remember my old ATi x800 happily outperformed the Quadro in my workstation, it's why I stopped using them in the first place, but that was a good 7 or 8 years ago, when I'd only been at this for about 15 years (See what I did there, you young whipper-snapper!

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All this advice needs to be taken with caution, I don't use NURBS, and the OP may need to, 3D Studio MAX
is optimised for gaming cards, and we don't know what the OP will use, I use creative suite a great deal, and Photoshop & Premier do make really good use of the cuda cores in my 690, but that's CS6,
not 5 or below,the OP may have no need for image manipulation. If the OP's workstation is for Microstation I don't have a clue what is best, same for Solid works, or a mysterious in house render engine built around an old renderman box. Most of my render work is for screen use, so I tend to output at around 2000 pixels wide, never more than 4000, so I don't need massive amounts of ram, FX work for film is going to be a lot bigger and so need more RAM, animation or stills, games or technical illustration.... and on.... and on..... and on.
I've been doing this for years, I know how to get the best out of my workstations, I still see the sales guys they still tell me 'You need a BoXX workstation with Quadro or a FireGL'. I try them, they aren't any better, faster, prettier, rinse and repeat every couple of years.
Of course, as far as the OP is concerned we could all be pre-pubescent trolls, making this stuff up for ***** & giggles & posting on an ipad, just saying....