I had a Barbie Pink guava for a few years which I eventually threw away. The fruits were huge in size and were occasionally good but usually very bland. It got morning sun but not a lot of afternoon sun. I have found the "Sweet Kiss" variety, sold by Top Tropicals, to be much better. Those fruits are small but are usually sweet with a berry flavor, unique for guavas. I have also had very good Ruby x Supreme guavas from Exotica Nursery but haven't not yet grown my own fruit of that variety so it's not quite a fair comparison.
