Its quite annoing to have several cameras setup and to be working on a model in perspective, and then have to switch to a camera to render, than move the perspective back, especially with several cameras.

The cameras should all be listed in the viewport dropdown, so they can be selected independently of the working environment.

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3DS Max Entertainment Creation Suite Subscription, BonesPro, FumeFX, Flatiron, Unity3d Pro
Windows 7 x64, 16GB, Quadro FX3800
Windows 7 x64, 12GB, GeForce GTX580

You know you can have up to 4 viewports, right?  So you can keep your Perspective view set for one, and switch one or more of the other views to your camera.

Alternatively, you could hit Ctrl-C to create a camera from your Perspective view, switch to your render camera, then back to the one you just created.  Delete that camera, and you are right back to your previous Perspective view.

Or… Use the Batch Render tool to set what camera to render, and it doesn’t need to be active in a viewport.

3DS Max Design 2011 64-bit - Advantage Pack
Dell Precision T5500, Dual Six Core Xeon X5650 @ 2.67GHz, nVidia Quadro 5000, 24 GB RAM, Win 7 Enterprise 64-bit
Minneapolis, MN, USA