Nobody likes a quitter. Line6 isn't the endall answer to the problem and certainly isn't the best direct in available.
If you can't get a good sound micing an amp then you either have bad mics, bad mic pre's, a bad amp, a good amp set up bad, a bad room, poor mic position or a combination of all of it. It could be just a lack of understanding on how to process the sound properly using compression and EQ. Because you're having difficulty in getting a good sound doesn't mean you should switch hit.
The best guitar sound 'can' be achieved by micing the amp and when you cop out to a line6, your just quitting on learning how to get that sound. You should keep working at it until you get a good sound from micing the amp and then switch if you prefer the Line6 but my guess is you won't.