My test was multiple choice, but you get a chance to defend your answers at the end because some of the questions are really ambiguous and require deep analytical thought. I think OPST has a practical component but I did not have that for OPSE and I'm not sure for OPSA.
ISECOM USA is the only US based trainer.
ISECOM USA Trainer
Periodically they do trainings in the US but not many. I've seen them at Black Hat Vegas before but it's been a couple years.
There's mention of a Shelton, CT - USA training for OPSA coming up but no date mentioned. I'd contact Chris Griffin or Pete Herzog directly to let them know you are interested.
chris dot griffin at isecom dot org
pete at isecom dot org
Or you can use the contact form at https://www.isecom.org/contact.shtml
If you get something going, let me know. I'm interested in OPSA and OPST as well. When I did OPSE it was pretty cool because a corporate customer backed out at the last minute so I got 1 on 1 with Chris at a nice beachside resort north of Tampa. ISECOM covered most of the meals as well as the hotel in the registration cost. Pete Herzog (who is one of the very few folks in the industry who I can honestly say is a "thought leader") dialed in on the last day and patiently answered all of my very ignorant questions. Really great experience!
CISSP, CISA, GPEN, GWAPT, GAWN, GCIA, GCIH, GSEC, GSSP-JAVA, OPSE, CSWAE, CSTP, VCP
WIP: Vendor WAF stuffhttp://sentinel24.com/blog