Capitol Armory usually runs a sale around 4th of July, a buy one get two or something and it's worth it to buy then. As far as 5.56 goes, the Sico Saker is a solid safe bet and I scored two of those for $1300 with mounts and ASR brakes.
I have an Omega 9k I swear by for 9mm, it's not the most quiet but it's not nine inches either. I also doubt it would be very useful on a 5.56 and I too believe in specific cans for specific jobs. The one multi use can I have is the one that gets used the least.
So I'd consider scoring something on sale for the 5.56 and something else for the .45. Also beware 10mm isn't a great caliber to suppress for two reasons, one is that it has a high pressure and two is that it also has high gas volume for a pistol round and that makes it less than ideal. I mean, folks do it but 9mm sub suppresses best followed by .45 with respect to the standard pistol calibers. I like 10's too but I don't bother suppressing those.
The 5" and 9" ultras were a good choice, I have those too and they're also great on .300BLK SBR's (very low gas volume, especially with subs).