I've very recently just flown in my first SQ suite (I've previously flown SQ's F B777 product multiple times, so I was really excited to finally try out their suite).
As much as I love the A380 (a piece of of engineering mastery) and SQ (never had a bad experience with them thus far), I have the possibly controversial opinion of preferring their First product to their Suites product.
The staff, food & drink, service, attention, access to The Private Room are amazing with both.
The amount of room you get with the suite, along with the privacy of the quite tall door, is also amazing.
What I wasn't so fond of was the sleeping orientation - rather than being in-line with the aircraft, you're at the opposite orientation. (I understand that it's done this way so that you can lower the partition and have a double suite with a double bed if you're travelling as a couple.) Therefore, as the plane rocks, it moves your body in an unusual way. I also found the bed to be on the harder side (certainly more so than the F product). I barely got any sleep, sadly. I accept that this could just be that I'm not used to it.
Another thing that I didn't quite like was that during take-off and landing, the seat and the tv need to be in their stowed positions (which makes sense), however, this makes it very uncomfortable to watch the tv with your neck at 90 degrees.
I understand that these things are very first-world problems. I am so fortunate that I was able to finally give it a go (I missed out last year due to a scheduling conflict). I love SQ, I love the A380. This is just my opinion. Thank you for listening.