I get very good results but do only paid work on my mabook pro, SU and Maxwell. I am restricted to show anything though. My work is for the government, office interiors. The results are so good that sometimes I see people just think I am showing actual photos.
My work flow is:
Make many small SU files with parts of the complete model. I merge all files in Maxwell Studio and position camera's, textures and materials in Studio. Quick and fast, thats what Studio is. Sometimes I position textures in SU when each face needs special attention like plywood with edges in different textures.
I never have any speed issue other than the rendering itself wich takes a couple of days. No problem since I only charge for modeling and texturing and not for the runtime rendering. The new 8-core macs will probably deal with the rendertimes in a way that those are no longer an issue.
All I can say is spend a good week or two full time with Maxwell and SU and you are on top of it. It should work fine on a Mac. Pavol is doing good work on a new plugin that will have most problems solved. You can ask him to send you the beta version.
Many try to render straight out of SU which to me is silly. Why go through the annoying export each time you want to do a testrender while you could have easily rendered without any problem large models in a snap out of Studio. Studio is a little intimidating at first but very simple actually. Studio is an application you need to master right- and left mouse click well. Some in combination with shift- option- control and command. That makes Studio not a typical Mac app. Still, now I understand how it works I love to work in Studio. The biggest problem rendering out of SU is that you need to export the whole model, especially large models need tweaking and testing. Taking smaller models from SU in Studio and test them first untill they are right is much easier and faster. I could go on and on on this issue but won't waist your time as you might already be working with Studio. Still when I see people hassling those big models in SU I do wonder what is wrong with them. Visualisation, modeling and rendering is organise 3D-data really.
In summary:
-Organise your models in easy to tweak and control parts.
-Use Studio to complete the model and render from.
-Study materials in such a way that you have organised them in the proper folders and name your materials in SU properly and in a way you can easily find them.
-Make small jpg's at the same dimensions to use in SU-color palette and convert materials on export into mxm materials.
-Use as few materials as possible, often there are too many materials without much effect.
-On every import in Studio organise your objects and materials. Delete duplicated materials or unused materials, cameras and objects.
-Group objects in Studio naming them.
-Use multi lighting to test render and adjust the emitters accordingly for the final rendering. Often I had some emitters much to strong. In multi lighting mode I saw that I just needed to tweak the emitters to work together in a more natural way. The final rendering I never use mulit light since it takes to much rendertime.
Hope this is of some help. This project was done only with SU and Maxwell by my office.
http://www.arkitekt.se/s26167/f3612
And I posed this before on the SU forum.
http://forum.sketchup.com/showthread.php?t=74715