I did a text search on avsforum and avforum. It did not find any reports of protection mode/transistor blown related issues. Then search Amazon 1/2 star rated reviews and found quite a few reports of having to send back for shutting down but no report of blown transistors (doesn't mean it didn't happen).
If you do a detailed text search you will find reports of the AV7702 (the AV7702 MkII was the equivalent AV to the SR7010) shutting down and other issues too though there were fewer (about half) 1-star ratings on Amazon than the SR version.
Don't forget the AV version of the SR differences are only/mainly in the following.
On the plus side:
The AV version does not need to deal with the heat from the power amp section, and it has more space to breathe too.
On the minus side:
- It has the unbalanced circuitry/components, and the associated additional heat from the additional HDAMs (though minor).
Overall, I highly doubt theoretically speaking the AV version would be that much more reliable than the SR version especially if external fan(s) is/are used.
TLSGuy: I strongly suggest you use an external fan if you want to external the life of your AV7705 unless it is very well ventilated. It may have a fan that is hidden from plain view but the schematics of the 7704 and even the 8805's schematics show there is "fan control". They do that for a reason, trouble is, they don't typically had the set point too high for my liking, obviously ymmv..
For most users in small to medium size room driving 8 ohm nominal speakers, an AVC such as the 7705 would run almost as warm as the SR7013. When I had the AV8801 for the HT I had to use two fans to make me feel like it would last forever, otherwise it just felt too warm to the touch but that's just me.