Try them yourself using Blender. There is a little learning curve but the software is free. The thing that I like about Blender is that you can use any image file and with some plug-ins you can also use cad files.
Google Sketchup has tremendous support and provides a full library of files that can easily be modified to meet your needs for floorplans. Once you download the program, you will have full access to the users library and support from other users. Of course, once you have learned from others, you will want to pay it forward in order to help others.
I haven't d/l any of the software yet. Will this allow you to take a picture of say a chiller and then import it and make it into a graphic? Kinda like what I attached? We had a RTU that a company did for us. when we sent the picture you could see foot prints on the white roof. When they sent the graphic back to us, there were the foot prints lol.
The attachment is chiller we have at one of our sites. We made the pic sent it to someone (I have no idea who or where, it was before my time here) and they sent this back. Will the software mentioned here do this?
To answer OP. We have used BAS Graphics (Alper and the gang), ControlGraphics and 1 or 2 local people. Both of the above have done a good to great job for us. The locals not so great.
The biggest Issue is YOU have to know what you want ! Things like color sets, what kind of extensions, etc. Do you want windows in your exterior walls, elevator shafts, entry doors, passage doors, duct runs displayed in relative sizes, different objects for VAV's and Fan Powered VAV's and so on.
Unless you have capability to re-size the *.jpg or *.png files you also need to tell your Graphics developer what the final size and resolution should be.
Over all I prefer ControlGraphics because I have been working with some of the indviduals for over 10 years. We have always gotten fast turn around on any thing we needed fixed.
Crap, I almost sound like a commercial for them! Sorry. JMO
If sense were so common everyone would have it !
All opinions expressed are my own. Any advice provided is based on personal experience, generally accepted fact or publicly available information. As such, it is worth exactly what you paid for it, not a penny more not a penny less !!
I have worked with Alpert at BAS Graphics on several occasions and was extremely pleased each time. Worth every penny compared to having an anal retentive non-artistic type like myself spend ridiculous amounts of time trying to get it just right.
I have no idea why anyone would want a 3D graphical floorplan.
I have seen them, it takes away from the data on the screen.
No operator would ever want them.
No controls tech would ever want them.
No mechanical tech would ever want them.
Unfortunately, none of them pay for the project.
That said, if the management/engineers/architects DO request 3D graphics, just make sure they are VERY overhead view, so they are almost 2D. This will maximize the utility of them, while still meeting the job's requirements.
On the same token, I hate 'realistic representations' of air handlers, RTU's, etc. They are no where near as useful as a simple rectangular duct cutaway.