2006 XC90 V8 Has anyone installed a block heater

[VFLXC90]

With my cold start issue. Engine noise. I'm planning an installation of a block heater. If the engine is warm the noise isn't there. So my temporary remedy is to do above. Volvo sells a heater for around $165.00. It appears to be a plug that has a heating element in it. The wire connects to the plug and it heats the coolant.
There are several manufactures of block heaters. Cat's and Zero Start are the two I've seen so far. Cat's is a universal design that splices into the heater hose. Seems to be straight forward. I'm Not sure were Cat's is manufactured? Zero Start also has a universal design. Install same as Cat's. Zero Start ,Canadian company. Zero Start also has what appears to be the same as the Volvo factory design . Zero start is around $75.00 for the heater and wire. It's Possible Zero Start supplies there part to Volvo? If you EBay: engine block heaters 3100002. (heater) 3600001 (wire to the heater). it will bring up Zero Start. You can open up the description and enter in the 06 XC 90 V8 and see the info Zero Start has for there application. From what I can tell there is a plug on the driver side rear head that there heater installs in? Doesn't seem to be a freeze plug that needs to be removed. Just a simple unscrewing of a plug, install the heater, connect the wire and good to go?
Based on the info above. Has anyone installed the factory heater, Zero Start heater or a universal heater.
Any info would be appreciated.
VFL