be advised that adding a non factory Fiesta seat in the ST will cause the airbags not to work, plus you would lose the side airbags. I have gone down the road of adding aftermarket seats to a modern car and it caused issues that made it not worth ever doing again. I would doubt you could buy a set of reclining Sparco seats for less than the upgrade charge of the Recaro seats. A fixed back seat without a roll bar is not very safe for the street. I may be Pro-Recaro, but I have also gone down the path of installing performance seats in a car with Gen2 airbags and ran into problems. It gets really fun trying to sell a car without airbags. It pretty much kills the resale. If you don't reconnect the sensors right if you put the normal seats back in, the fuses blow and they are expensive to replace. Unless I was building a show or dedicated track/race car, I would not replace the seats. Now, you could buy a set of Recaro seats from the junkyard. You would need the matching rears to go with it, plus the heated seat switches, and then wire it all in.
You wanted input from a ST owner without the Recaro seats, well, I have a 2011 Fiesta with the same seat as the ST base has. I have autocross and tracked both cars, so I have a pretty good understanding of both seats. I have logged over 46,000 miles in the base seat and 6,000 miles in the ST seat. Both tracked, both autocrossed, both driven on road trips, and both have had a number of different passengers.
