Miking solid state amps

Shouldn't really matter if you're using a high quality microphone. A good microphone will be able to withstand the volume levels your amp will throw at it without the sound levels causing breakup.
 
As long as you're using a dinamic microphone, such as a Sure SM57, it wont really matter in terms of the mic. Just have the amp volume at its "sweet" spot, where the speaker/ amp doesnt start to shit itself and lose clarity, bottom end, or start to have realy shrill highs.
If you want to keep a nice "thick" sound, try deadening the area around the amp with pillows and shit, or throw a blanket/ duna over the amp.
And if you're a 'lil new to micing, make sure you do a bit of testing before you settle on a sound, move the mic around and listen to whay effect it has on the sound, but generally for metal, you want the mic on axis, directed at the cone about an inch to an inch and a half from the outside edge of the cone.

Good Luck

Daniel\m/