Well, you know I am the only one running Avionixx. Nobody understands them, they can be quirky at times but I have had very good luck with mine. At least until you borrowed that last one.
I am running my Wetsounds off a special Avionixx AXT 1000.4. Before that they were running off a AXT 800.4. The 800.4 does 400x2 bridged the 1000.4 does 500x2 bridged. Try the 800.4, see if you like it. They still have some left at woofersetc for $250. That's the cheapest most high-efficient power you can find. If there is something better for close to that price I would like to find it.
Including the one you cooked last weekend with your 6x9s, I have burned up 3 tripath amps. They have all burned up right away when they did not like the load. The ones currently in my boat are going on their fourth season with the excpetion of the 1000.4 that I just installed over the winter. The 800.4 you borrowed to test has three hard seasons on it, it is the amp that ran my tower speakers. The other 800.4 running my boat is still doing fine.
My equipment falls into one of two categories. Disposable or replaceable from the manufacturer. Either way, I push my equipment pretty hard, when it breaks, it gets replaced.
I am still waiting for the little sub box to burn up. It's surprising that it has lasted for two full seasons.