Oscar vs harmony test - which should I go for? Price diff is substantial!

my 2 cents - If you are below 35 - the risk of down syndrome is very low (1/1200), so you can do oscar first, and only if you have an unfavourable result then go for harmony to confirm (since oscar is 99% accurate only). If you are above 35, go straight to harmony since you run a higher risk (1/350, higher if you are older) - i.e. even if you have a good oscar result, you might still be worried it is wrong (99% accuracy), you might as well have the peace of mind and get a 100% confirmed harmony test result straight a way, if the cost is not prohibitive to you