I was hopeful, I stacked 5, and after extensive testing on 3 sites, the final results showed Gumlet was consistently the slowest load time for each site. I gave their support full admin access and several weeks to review and recommend changes, and after being told twice that all was installed well and nothing better could be expected, I decided to get a refund.

More details below for those who are curious:

1. I tested 3 wordpress sites - each in Australia
2. Each site was in a different state of 'well optimised' to 'poorly optimised' to give variety to the test.
3. Each site was tested with 3 different plugins (obviously one at a time) - "Gumlet", "Shortpixel" and "Compress JPEG & PNG images"
4. No other changes were made during the test - only ONE plugin was changed and retested.
5. Three speed test results taken from GTmetrix, Google Pagespeed Insights and webpagetest.org.

Result - site load time was consistently slower with Gumlet in each test.

Also Poor Support: My VA put in a support request which took a week to get a response. The response felt very dismissive - they just said it's installed properly and the best the plugin can do (without much more dialogue). It just seemed strange after the effort, the full access we offered and the full test results we provided that they came back with such a limited reply.

We thought we might have misunderstood and still wanted to give them the benefit of the doubt, so we asked them for some clarification, and after waiting 2 weeks my VA gave up waiting.

As a last ditch effort, I sent a seperate email saying I would be seeking a refund if there was nothing else that could improve the results and it was only after another week of waiting that Divyesh (the owner) replied saying Gumlet can only do so much and the sites needed more work than what Gumlet could do.

He was polite and the answer was fair enough - it's true that the sites needed more work than what Gumlet could do - however I wasn't asking for perfection. I was asking why Gumlet did so poorly compared to the others.

Regardless of how the site was optimised, it still showed that Gumlet was not up to par with the other 2 plugins.

But even the one site that Divyesh said was 'super optimized' could not be improved with Gumlet (but could be improved using the other 2 plugins).

So bottom line - unusable for me. I might have given them 3 Tacos since the product does work (even though it's not great) but the super slow support was sooooo slow, that I had to drop another Taco for the poor support. It's just a very poor combination.