I have a biorb Mine's tropical though. For two goldies you should really get the 60L biorb as they need lots of space (ideally 10 gallons/38L per goldie) (I wish I'd got the bigger one from the word go, as well). Aqua One tanks are also very nice.
Disadvantage of the biorb is that the filter is right at the bottom so you need to get your arm wet for filter changes, often moving decor to reach it. Otherwise they are lovely tanks (ignore what they say about only cleaning once a month though - my 30L definitely needs cleaning once a week and I have tropicals - goldfish are much messier).
Make sure you take something over of your old tank so the good bacteria gets transfered over and avoid new tank syndrome (a sponge from your old tank... some gravel tied in an old sock (can't use gravel any smaller than a large peain a biorb as it gets stuck in the filter)... and pass over the old water). Be prepared to test the water and do lots of partial water changes until the water parameters settle.
Oh if you get the biorb, get the LED lighting ... you get moonlight blue in the evenings it's lovely. With real plants though you'll need to go for the extended daylight setting and stick to plants that can thrive in low light.