I have owned a Splawn Competition and currently own a Splawn-Modded Marshall 1959SLP Reissue. As everyone has already mentioned, Scott is a great builder and someone you can reach on the phone while having your amp built. He has alot of patience. His amps, especially the Quick Rod and Pro Mod, have gotten alot of praise for their ability to get the articulation, etc. of late 70's, early 80's hard rock.
Several of my friends own Camerons and I have been able to run them thru their paces with different guitars, speakers, etc. There is something inside a Cameron's tone that just sounds "polished" in my opinion. A Cameron has that "George Lynch cranked on a stage in front of 100,000 people" sound. It just sounds like a wall of awesome tone. It is hard to explain. There are frequencies and EQ settings that just capture the "holy crap!!" tone that makes you want to reach for your wallet.
The Splawn amps sound outstanding as well but for me personally, don't outdo the Cameron tone. I'm probably way off here with this comparison but to me, the Splawn tone sounds more like a Van Halen I tone whereas the Cameron sounds more like a "Woman and Children First" and "1984" type of tone.
If you can find a Cameron (good luck) then I would by that first. I don't think you would be disappointed with a Splawn though.