Which PCB Fabrication / Manufacturer do you use?

Indeed there are a lot of different vendors out there and for prototyping purposes they all appear pretty good and I find myself choosing based on delivery cost and speed of delivery.

Personally, I like https://oshpark.com/ but then found my postal service charging me additional fees for larger orders as I'm in the EU and they are in the US.

Then there's https://aisler.net/ who are EU based seem to be continually improving with their service offering. Liking them more and more.

Then of course there's JLPCB, PCBWay, Seeed and Elecrow who all provide good service but sometime delivery gets in the way.

Indeed there are a lot of different vendors out there and for prototyping purposes they all appear pretty good and I find myself choosing based on delivery cost and speed of delivery.

Personally, I like https://oshpark.com/ but then found my postal service charging me additional fees for larger orders as I'm in the EU and they are in the US.

Then there's https://aisler.net/ who are EU based seem to be continually improving with their service offering. Liking them more and more.

Then of course there's JLPCB, PCBWay, Seeed and Elecrow who all provide good service but sometime delivery gets in the way.

I have only used JLCPCB, to make 2-layer, 4-layer and very recently a 1-layer ALU pcb to use for an enclosure panel.  The prices are excellent, especially for boards that are up to 100mm square, even 4-layer.  So far, I've had around 10 different designs created and quality has always been very good.  They are based in China so shipping depends upon options used.  If I used a courier such as Fedex or DHL I've had turn around to my door in the UK in under a week!  This tends to be expensive: say, circa £30 shipping for £2 PCBs.  Regular postage takes around 3 weeks turn around to my door and is cheap.  JLCPCB will collect any taxes or fees at point of order so you don't need to pay the courier's processing fee on top.

My last order with them was for the ALU panel.  The design had no solder mask on the back side so the Gerber for this was 'empty'.  This caused problems with their auto-processing because it doesn't seem able to deal with that perfectly valid situation.  I was contacted by them within 24 hours to explain my options and ask me what I wanted to do, including "fixing" and re-uploading.  I just told them to cover the back side with solder mask and let them get on with it and there were no problems.

For 2-layer boards <= 100mm square I don't think the price and quality can be beaten.  I'd wholly recommend them.

Similar experience here, super-happy with the speed with them - my last order, via FedEx, from date of ordering (on a Saturday), to receiving it in the post, was just under 9 days, and cost me $26.72 (all-inclusive, including shipping) for two different PCBs, in a qty of ten and five. These boards were HASL, 2-layer, smaller than 100x100mm, in black and blue solder mask. 

In Czechia (EU) I also faced additional postal fee (which in fact was higher than the value of the order...), but later I found government online portal which allows me register incomming package and pay VAT on my own reducing need to do this by czech post and pay high fee to them. This reduced additional price significantly. I recommend checking on this in your country.

Thanks, I'll have to check that out.