Sysadmin How to check that CloudFlare is working properly with PageSpeed?

I recently setup CloudFlare on one of my domains that also takes advantage of Nginx PageSpeed. I have Wordpress installed on the root directory as well as some other sub-folders hosting static content.

Upon inspection of headers, I see:
x-page-speed: 1.12.34.2-0
server: cloudflare-nginx

---

Cool, looks good.
However, none of my static resources like images/css/etc appear to have been rewritten by PageSpeed i.e. check.png becomes xcheck.png.pagespeed.ic.v1ImpeEk3F.png,

How do I know if CloudFlare is serving the non-optimized assets or if it is serving PageSpeed assets?

 

Yes I'm aware of this, but even after numerous reloads I don't see any PageSpeed specific assets.
I will try to purge all Cloudflare cached content and maybe it will push the PageSpeed stuff to their servers?

 

Hmm seems like a lot of errors
- No permission to rewrite
- HTTPCache key=... fragment=...: remembering recent failure for 247 seconds.
- Could not rewrite resource in-place because URL is not in cache

In pagespeed.conf I have

Oh also...is PageSpeed only beneficial for return visitors or will the optimized images/file formats/js/css be served to first time visitors as well?

 

Code (Text):

# service memcached status
Memcached server is running

Cool, good to know about the 1st time visitors

 

I don't think they are actually stripping the x-page-speed header. Here is a different site of mine on CF.

HTML

Code:

X-Page-Speed: 1.12.34.2-0
Cache-Control: max-age=0, no-cache
Server: cloudflare-nginx
CF-RAY: 3408j63jb2586dab-SKF

Static Asset (PageSpeed optimized) ximg1.png.pagespeed.ic.Vs-V_tWz_E.webp

Code:

Content-Type: image/webp
Access-Control-Allow-Origin: *
Expires: Mon, 16 Apr 2018 17:24:52 GMT
ETag: W/"0"
Cache-Control: public, max-age=31536000
X-Page-Speed: 1.12.34.2-0
CF-Cache-Status: HIT
Server: cloudflare-nginx
CF-RAY: 3902f631243b9dba-SJC

Edit: I actually don't know why this site is working with PageSpeed and Cloudflare and my other site isn't.